<PAGE>   1

                                                                    EXHIBIT 10.8

                            ALAMOSA OPERATIONS, INC.
                             4403 Brownfield Highway
                              Lubbock, Texas 79407


July 31, 2000

Washington Oregon Wireless, LLC
5665 SW Meadows Road, Suite 100
Lake Oswego, Oregon  97035
Attn: Mitchell Moore, Chief Executive Officer

Re:   Loan Agreement

Dear Mr. Moore:

     The undersigned, Washington Oregon Wireless, LLC ("BORROWER"), a limited
liability company duly organized, existing, and in good standing under the laws
of the State of Oregon, has entered into an Agreement and Plan of Reorganization
(the "MERGER AGREEMENT") pursuant to which Borrower will merge (the "PARENT
MERGER") with and into Alamosa Holdings, Inc. ("SUPERHOLDINGS") simultaneously
with the merger (the "SUBSIDIARY MERGER," together with the Parent Merger, the
"MERGERS") of a wholly-owned subsidiary of Superholdings with and into Alamosa
PCS Holdings, Inc., a Delaware corporation ("ALAMOSA"). In connection with the
execution of the Merger Agreement, Borrower and Alamosa Operations, Inc., a
Delaware corporation and a subsidiary of Alamosa (in its capacity as Manager
thereunder, "MANAGER") have entered into a Services Agreement (herein so called)
pursuant to which Manager shall manage the operations of Borrower.

     Borrower has requested that Alamosa Operations, Inc. (in its capacity as
Lender hereunder, "LENDER"), extend credit to Borrower to enable Borrower to
borrow on and after the date of this Agreement a principal amount not to exceed
$11,000,000, only for the purposes of (i) satisfying capital contribution
requirements under the Operating Agreement of Borrower, and (ii) funding
Borrower's working capital needs from the date hereof through the consummation
of the Parent Merger (the "MERGER DATE"). Lender has advised Borrower that
Lender is willing to advance such funds to Borrower upon the terms and subject
to the conditions set forth in this letter agreement (this "AGREEMENT"). Lender
and Borrower acknowledge and agree that on the Merger Date, all amounts due to
Lender by Borrower may, at Lender's option, be deemed paid in full and, in such
case, all funds advanced by Lender to Borrower hereunder and all accrued
interest thereon (the "MERGER DATE LOAN BALANCE") shall be characterized for all
purposes as capital contributions by Lender to Borrower. If, on the Merger Date,
Lender elects not to characterize the Merger Date Loan Balance as a capital
contribution, such amount shall remain a debt obligation of Borrower, subject to
the terms and conditions of a subordination agreement in favor of, and in form
and substance acceptable to, the senior lender to Alamosa Holdings, Inc., (the
"SENIOR LENDER SUBORDINATION AGREEMENT"). In consideration for the above
premises and the mutual promises and covenants herein contained, Borrower and
Lender agree as follows:

     1. Loan. On the terms and subject to the conditions hereinafter set forth,
Lender agrees to lend to Borrower, in multiple advances (each an "ADVANCE") to
be made, from time to time, on or before the Merger Date the sum of up to
$11,000,000 (the "LOAN").



<PAGE>   2

     2. Manner of Borrowing.

     (a) Notice of Borrowing. (i) Before the first day of the Term of the
Services Agreement, Borrower or (ii) on or after the first day of the Term of
the Services Agreement, Manager, acting on behalf of Borrower under the Services
Agreement, shall (x) give Lender a notice (a "NOTICE OF BORROWING") signed by
Manager and Borrower calling for an Advance on or before 10:00 a.m. (Dallas,
Texas time) two days before the requested Advance is to be funded, (y) specify
in the Notice of Borrowing the aggregate amount, requested date, and the
intended use of the Advance, and (z) certify that the representations and
warranties contained in each of the Loan Documents (defined below) are true in
all material respects as though made on the date of the Notice of Borrowing.
Borrower shall have no independent right to call for Advances, other than to
request Advances to fund capital contribution requirements if Manager does not
do so.

     (b) Minimum Advances; Number of Advances. Each Advance hereunder shall be
in a minimum amount of $1,000,000, and no more than two Advances each calendar
month may be requested or funded.

     (c) Funding. Subject to the terms and conditions in this Agreement not
later than 2:00 p.m., Dallas, Texas time, on the date specified, Lender shall
make available to Borrower, at Lender's offices in Lubbock, Texas, the amount of
a requested Advance in immediately available funds.

     3. Promissory Note, Interest, and Payments.

     (a) Note. The Loan shall be evidenced by a promissory note in the form of
EXHIBIT A, duly executed by Borrower (together with any renewals and extensions
thereof, the "NOTE"), dated the date hereof, in the principal amount of
$11,000,000, and payable to the order of Lender.

     (b) Interest Rate. Before the occurrence of an Event of Default, each
Advance shall bear interest at a rate per annum, calculated from day to day and
computed from the date of advance until repaid, equal to the lesser of (i) the
maximum lawful rate under applicable law (the "MAXIMUM RATE") or (ii) the per
annum rate of interest established from time to time by Bank of America, N.A.,
as its prime rate, which rate may not be the lowest rate of interest charged by
Bank of America, N.A. to its customers (the "BASE RATE"). Any past-due principal
debt and all past-due interest accruing thereon shall bear interest from
maturity (stated or by acceleration) at a rate per annum equal to the lesser of
(i) the Maximum Rate or (ii) the Base Rate plus 5%.

     (c) Payments.

         (i) Interest. Interest on the unpaid principal of the Loan shall be due
     and payable on the earlier of (A) date designated as 30 days after the
     termination of the Merger Agreement in a written notice delivered by Lender
     to Borrower advising Borrower that the Merger Agreement is being terminated
     and that the Parent Merger will not be consummated or (B) the effective
     date of any acceleration of any of the Obligation (defined below) (the
     "MATURITY DATE"); provided however that if, on the Merger Date, Lender
     elects not to characterize the Merger Date Loan Balance as a capital
     contribution, the Loan shall become a demand obligation, subject to the
     terms of the Subordination Agreements (defined below).

                                       2


<PAGE>   3

         (ii) Principal. The entire unpaid principal balance of the Loan,
     including all accrued but unpaid interest thereon, shall be due and payable
     on the Maturity Date or, in the event the Loan continues after the Merger
     Date, upon demand.

         (iii) Optional Prepayments. Borrower shall have the right, from time to
     time before the Maturity Date or payment of the Loan is otherwise demanded,
     to prepay the Loan, in whole, without premium or penalty, upon the payment
     of all principal and accrued interest on the amount prepaid to and
     including the date of payment.

         (iv) General Payment Terms. All payments on the Loan shall be made to
     Lender at its principal office in Lubbock, Texas in federal or other
     immediately available funds, and payments shall be applied first to accrued
     interest and then to principal. If any payment is scheduled to become due
     and payable on a day that is not a business day, that payment shall instead
     become due and payable on the immediately following business day, interest
     shall be payable with respect to the extension, and interest on the
     principal portion of the payment shall be payable at the then applicable
     rate during the extension. Interest on the Loan shall be calculated on the
     basis of a year of 360 days for the actual number of days (including the
     first but excluding the last) elapsed, unless the Maximum Rate shall be in
     effect, in which case on the basis of a year of 365 or 366 days, as the
     case may be.

     4. Conditions Precedent.

     (a) Initial Advance. The obligation of Lender to make its initial Advance
is subject to the conditions that (i) Lender has received duly executed copies
of each of the documents listed on SCHEDULE 4, each in form and substance
satisfactory to Lender and its legal counsel (those documents [except ITEM 8],
together with this Agreement, and any modifications thereof, collectively, the
"LOAN DOCUMENTS"), (ii) all consents to the transactions contemplated by the
Merger Agreement have been obtained from the parties to the agreements listed on
SCHEDULE 13.1 of the Services Agreement, and (iii) either (A) the waiting period
prescribed by the Hart-Scott-Rodino Antitrust Improvements Act of 1976 and the
rules and regulations promulgated thereunder (the "HSR ACT") has expired or (B)
early termination of the waiting period under the HSR Act has been granted.

     (b) All Advances. The obligation of Lender to make any Advance under this
Agreement (including the initial Advance) is subject to the conditions precedent
that, as of the date of the Advance and after giving effect thereto: (i) there
exists no "EVENT OF DEFAULT" (defined below) hereunder or under any other Loan
Document, or event which, with the giving of notice or passage of time or both
could become an Event of Default (a "POTENTIAL DEFAULT"); (ii) there exists no
default or event which, with the giving of notice or passage of time or both
could become a default under the loan agreement, dated as of April 12, 2000,
between Borrower and CoBank, ACB (the "EXISTING LOAN AGREEMENT"); (iii) there
exists no default or event which, with the giving of notice or passage of time
or both could become a default under the agreements between Borrower and parties
listed on SCHEDULE 13.1 to the Services Agreement; (iv) Lender shall have
received from Manager (or Borrower if before the first day of the Term of the
Services Agreement) a Notice of Borrowing and all of the statements contained in
the Notice of Borrowing shall be true and correct; and (v) the representations
and warranties contained in each of the Loan Documents shall be true in all
material respects as though made on the date of the Advance.

                                       3


<PAGE>   4

     5. Representations and Warranties. To induce Lender to make the Loan
hereunder, Borrower represents and warrants to Lender, subject to the provisions
of the Merger Agreement and the Disclosure Schedules relating thereto, that:

     (a) The Loan Documents are the legal and binding obligations of Borrower,
enforceable in accordance with their respective terms, except as limited by
bankruptcy, insolvency or other laws of general application relating to the
enforcement of creditors' rights; Borrower and each Guarantor has full power and
authority to execute and deliver the Loan Documents and to incur and perform the
obligations provided for therein;

     (b) Neither the execution and delivery of this Agreement and the other Loan
Documents, nor consummation of any of the transactions herein or therein
contemplated, nor compliance with the terms and provisions hereof or thereof,
will contravene or conflict with any provision of law, statute, or regulation to
which Borrower is subject or any judgment, license, order or permit applicable
to Borrower or any indenture, mortgage, deed of trust or other instrument to
which Borrower may be subject or to which Borrower may be a party; no consent,
approval, authorization or order of any court, governmental authority, or third
party is required in connection with the execution and delivery by Borrower of
this Agreement or any of the other Loan Documents or to consummate the
transactions contemplated herein or therein (and such consents are set forth on
SCHEDULE 5(B));

     (c) Upon the delivery of each Notice of Borrowing, there shall exist no
breach of any representation or warranty or nonperformance of any covenant or
agreement of Borrower under the Merger Agreement, except as affected by the
transactions contemplated by the Merger Agreement and except as will not
constitute a LLC Material Adverse Change (as defined in the Merger Agreement);

     (d) There is no fact known to Borrower that Borrower has not disclosed to
Lender in writing which may result in any material adverse change in Borrower's
business, properties, or operations;

     (e) No certificate or statement herewith or heretofore delivered by
Borrower to Lender in connection herewith, or in connection with any transaction
contemplated hereby, contains any untrue statement of a material fact or fails
to state any material fact necessary to keep the statements contained therein
from being misleading;

     (f) Each Notice of Borrowing shall constitute, without the necessity of
specifically containing a written statement, a representation and warranty by
Borrower that no Potential Default or Event of Default exists, and that all
representations and warranties contained in the Loan Documents are true and
correct on and as of the date the requested Advance is to be made, except to the
extent any such representations and warranties are expressly stated to be made
as of another date; and

     (g) All representations and warranties by Borrower herein shall survive
delivery of the Note and the making of the Loan, and any investigation at any
time made by or on behalf of Lender shall not diminish Lender's right to rely
thereon.

     6. Guaranties. To secure the full and complete performance by Borrower of
the payment and performance of the Loan and all other liabilities and
obligations of Borrower under this Agreement and the Note (the "OBLIGATION") if
the Parent Merger is not consummated, certain Members of Borrower that are
indicated on SCHEDULE 6 (as amended from time to time to add Guarantors) (each
such Member, a

                                       4


<PAGE>   5

"GUARANTOR") have executed and delivered (or, in the case of future Guarantors,
will execute and deliver) to Lender a Guaranty in the form of EXHIBIT C (a
"GUARANTY").

     7. Affirmative Covenants. Until payment in full of the Obligation, Borrower
agrees and covenants that (unless Lender otherwise consents in writing):

     (a) Borrower shall use all proceeds of the Loan solely for the purposes
described in the second paragraph of this Agreement;

     (b) Borrower shall conduct its business in an orderly and efficient manner
consistent with good business practices and in accordance with all valid
regulations, laws, and orders of any governmental authority and will act in
accordance with customary industry standards in maintaining and operating its
assets, properties, and investments;

     (c) Borrower shall maintain complete and accurate books and records of its
transactions in accordance with generally accepted accounting principles, and
will give Lender access during business hours to all books, records, and
documents of Borrower and permit Lender to make and take away copies thereof;

     (d) Borrower shall furnish to Lender the financial statements required
pursuant to Section 8.4 of the Merger Agreement;

     (e) Borrower shall furnish to Lender as soon as available and in any event
within ninety days after the close of each fiscal year of Borrower, copies of
the balance sheet of Borrower as of the close of such fiscal year, and
statements of income and retained earnings and changes in financial position of
Borrower for such fiscal year, in each case setting forth in comparative form
the figures for the preceding fiscal year, all in reasonable detail and
accompanied by an opinion thereon (which shall not be qualified by reason of any
limitation imposed by Borrower) of Aldrich Killbride & Tatone LLP or of other
independent public accountants of recognized national standing selected by
Borrower and satisfactory to Lender, to the effect that such financial
statements have been prepared in accordance with generally accepted accounting
principles consistently applied and that the examination of such accounts in
connection with such financial statements has been made in accordance with
generally accepted auditing standards;

     (f) Borrower shall furnish to Lender, immediately upon becoming aware of
the existence of any condition or event constituting an Event of Default or
Potential Default, written notice specifying the nature and period of existence
thereof and any action which Borrower is taking or proposes to take with respect
thereto;

     (g) Borrower shall promptly notify Lender of (i) any material adverse
change in its financial condition or business; (ii) any default under any
material agreement, contract or other instrument to which Borrower is a party or
by which any of its properties are bound, or any acceleration of any maturity of
any indebtedness owing by Borrower, (iii) any material adverse claim against or
affecting Borrower or any of its properties; (iv) any Event of Default, any
Potential Default, or any default under any other Loan Document; and (v) any
litigation, or any claim or controversy which might become the subject of
litigation, against Borrower or affecting any of Borrower's property, if such
litigation or potential litigation might, in the event of an unfavorable
outcome, have a material adverse effect on Borrower's financial condition or
business or might cause an Event of Default;

                                       5


<PAGE>   6

     (h) Borrower shall promptly furnish to Lender, at Lender's request, such
additional financial or other information concerning assets, liabilities,
operations, and transactions of Borrower as Lender may from time to time
reasonably request;

     (i) Borrower shall promptly pay all lawful claims, whether for labor,
materials or otherwise, which might or could, if unpaid, become a lien or charge
on any property or assets of Borrower, unless and to the extent only that the
same are being contested in good faith by appropriate proceedings and reserves
deemed adequate by Lender have been established therefor;

     (j) Borrower shall maintain on its properties insurance of responsible and
reputable companies in such amounts and covering such risks as is acceptable to
Lender, is prudent and is usually carried by companies engaged in similar
businesses; Borrower shall furnish Lender, on request, with certified copies of
insurance policies or other appropriate evidence of compliance with the
foregoing covenant; and

     (k) Borrower shall preserve and maintain all licenses, privileges,
franchises, certificates, and the like necessary for the operation of its
business.

     8. Negative Covenants. Until payment in full of the Obligation, except as
otherwise permitted under the Existing Loan Agreement, Borrower covenants that
it shall not (unless Lender otherwise consents in writing):

     (a) incur or assume any indebtedness or borrow money;

     (b) mortgage, assign, encumber, hypothecate or grant a security interest in
any of Borrower's assets, except for liens and security interests securing
payment of Borrower's obligations under the Existing Loan Agreement (provided,
however, that the foregoing shall not apply to inchoate liens for taxes which
are not delinquent or which are being contested in good faith and liens
resulting from deposits to secure the payments of workmen's compensation or
social security or to secure the performance of bids or contracts in the
ordinary course of business);

     (c) liquidate, dissolve, or reorganize, merge or consolidate with, or
acquire all or substantially all of the assets of, any other company, firm, or
association (except as contemplated by the Merger Agreement); or make any other
substantial change in its capitalization or its business;

     (d) pay any dividends on any of its outstanding stock, or purchase, redeem,
or repurchase any of its stock;

     (e) sell any of its assets used or useful in its business, except in the
ordinary course of business; or sell any of its assets to any other person, firm
or corporation with the agreement that such assets shall be leased back to
Borrower (except as contemplated by the Merger Agreement); or

     (f) own, purchase, or acquire, directly or indirectly, any promissory
notes, stock, or securities of any other person, firm, or corporation, other
than securities guaranteed as to the principal and interest by the United States
government; or make any loans or advances to any other person.

     9. Default. An "EVENT OF DEFAULT" shall exist if any one or more of the
following events (collectively, "EVENTS OF DEFAULT") occurs:


                                       6


<PAGE>   7

     (a) Borrower fails to pay when due any principal of, or interest on, the
Note or any other fee or payment due hereunder or under any other Loan Document;

     (b) any representation or warranty made in any of the Loan Documents proves
to be untrue or inaccurate in any material respect as of the date on which such
representation or warranty is made;

     (c) default occurs in the performance of any of the covenants or agreements
of Borrower contained in SECTIONS 7(b), (c), (j), or (k) and such default is not
cured within 30 days of receipt by Borrower of notice, oral, or written, of any
such default;

     (d) default occurs in the performance of any of the covenants or agreements
of Borrower contained herein (other than those set forth in SECTIONS 7(b), (c),
(j), or (k)) or in any other Loan Document;

     (e) Borrower or any Guarantor (i) applies for or consent to the appointment
of a receiver, custodian, trustee, intervenor, or liquidator of itself or
himself or of all or a substantial part of its or his assets, (ii) voluntarily
becomes the subject of a bankruptcy, reorganization, or insolvency proceeding or
is insolvent or admits in writing that it or he is unable to pay its or his
debts as they become due, (iii) makes a general assignment for the benefit of
creditors (iv) files a petition or answer seeking reorganization or an
arrangement with creditors or to take advantage of any bankruptcy or insolvency
laws, (v) files an answer admitting the material allegations of, or consent to,
or default in answering, a petition filed against it or him in any bankruptcy,
reorganization, or insolvency proceeding, (vi) becomes the subject of an order
for relief under any bankruptcy, reorganization, or insolvency proceeding, or
(vii) fails to pay any money judgment against it or him before the expiration of
30 days after such judgment becomes final and no longer subject to appeal;

     (f) an order, judgment, or decree is entered by any court of competent
jurisdiction or other competent authority approving a petition appointing a
receiver, custodian, trustee, intervenor, or liquidator of Borrower or any
Guarantor or of all or substantially all of its or his assets, and such order,
judgment or decree continues unstayed and in effect for a period of 30 days; or
a complaint or petition is filed against Borrower of any Guarantor seeking or
instituting a bankruptcy, insolvency, reorganization, rehabilitation, or
receivership proceeding of any of them, and such petition or complaint is not
have dismissed within 30 days;

     (g) Borrower defaults in the payment of any material indebtedness of
Borrower or in the performance of any of Borrower's material obligations and
such default continues for more than any applicable period of grace;

     (h) an event of default has occurred and is continuing under the Existing
Loan Agreement; or

     (i) a breach or an event of default under the Services Agreement by
Borrower that could give Manager the right to terminate the Services Agreement
has occurred and is continuing.

     10. Remedies Upon Event of Default. If an Event of Default has occurred and
is continuing, then Lender at its option may (i) declare the principal of, and
all interest then accrued on, the Loan and any other liabilities of Borrower to
Lender to be forthwith due and payable, whereupon the same shall forthwith
become due and payable without notice, presentment, demand, protest, notice of
intention to accelerate, notice of acceleration, or other notice of any kind,
all of which Borrower hereby expressly waives, anything

                                       7


<PAGE>   8

contained herein, in the Note, or in any other Loan Document to the contrary
notwithstanding, (ii) reduce any claim to judgment, and/or (iii) without notice
of default or demand, pursue and enforce any of Lender's rights and remedies
under the Loan Documents or otherwise provided under or pursuant to any
applicable law or agreement.

     11. Miscellaneous.

     (a) Waiver. No failure to exercise, and no delay in exercising, on the part
of Lender, any right hereunder shall operate as a waiver thereof, nor shall any
single or partial exercise thereof preclude any other or further exercise
thereof or the exercise of any other right. The rights of Lender hereunder and
under the other Loan Documents shall be in addition to all other rights provided
by law. No notice or demand given in any case shall constitute a waiver of the
right to take other action in the same, similar or other instances without such
notice or demand.

     (b) Notices. Any notices or other communications required or permitted to
be given by any of the Loan Documents must be given in writing and must be
personally delivered, telecopied (with an original notice delivered by overnight
courier service), or mailed by prepaid certified or registered mail to the party
to whom such notice or communication is directed at the address of such party
set forth on the signature page to this Agreement. Any such notice or other
communication shall be deemed to have been given on the day it is received as
aforesaid. Any party may change its address for purposes of this Agreement by
giving notice of such change to all other parties pursuant to this SECTION
11(b).

     (c) Governing Law. This Agreement and the other Loan Documents are being
executed and delivered, and are intended to be performed, in Lubbock County, in
the State of Texas, and the substantive laws of Texas shall govern the validity,
construction, enforcement and interpretation of this Agreement and all other
Loan Documents, except to the extent: (i) the federal laws governing national
banks expressly supersede and have contrary application; or (ii) federal laws
governing maximum interest rates shall provide for rates of interest higher than
those permitted under the laws of the State of Texas.

     (d) Invalid Provisions. If any provision of this Agreement is held to be
illegal, invalid, or unenforceable under present or future laws effective during
the term of this Agreement, such provision shall be fully severable and this
Agreement shall be construed and enforced as if such illegal, invalid or
unenforceable provision had never comprised a part of this Agreement, and the
remaining provisions of this Agreement shall remain in full force and effect and
shall not be affected by the illegal, invalid, or unenforceable provision or by
its severance from this Agreement.

     (e) Maximum Interest Rate. Regardless of any provisions contained in this
Agreement, the Note, or in any of other Loan Documents, Lender shall never be
deemed to have contracted for or be entitled to receive, collect, or apply as
interest on the Note, any amount in excess of the maximum rate of interest
permitted to be charged by applicable law, and, if Lender ever receives,
collects, or applies as interest any such excess, such amount which would be
excessive interest shall be deemed to be a partial prepayment of principal and
treated hereunder as such, and, if the principal balance of the Note is paid in
full, any remaining excess shall forthwith be paid to Borrower. In determining
whether or not the interest paid or payable under any specific contingency
exceeds the highest lawful rate, Borrower, and Lender shall, to the maximum
extent permitted under applicable law, (i) characterize any non-principal
payment (other than payments which are expressly designated as interest payments
hereunder) as an expense, fee, or premium, rather than as interest,

                                       8


<PAGE>   9

(ii) exclude voluntary prepayments and the effect thereof, and (iii) spread the
total amount of interest throughout the entire contemplated term of the Note so
that the interest rate is uniform throughout such term.

     (f) Subordination. Lender acknowledges that the Obligation of Borrower
under this Agreement shall be subordinated in right of payment to the Existing
Loan Agreement and will execute documents reasonably acceptable to Lender in
order to memorialize that subordination (the "EXISTING LOAN SUBORDINATION
AGREEMENT," together with the Senior Lender Subordination Agreement, the
"SUBORDINATION AGREEMENTS").

     (g) Entirety and Amendments. The Loan Documents embody the entire agreement
between the parties and supersede all prior agreements and understandings, if
any, relating to the subject matter hereof and thereof, and this Agreement and
the other Loan Documents may be amended only by an instrument in writing
executed by the party, or an authorized officer of the party, against whom such
amendment is sought to be enforced.

     (h) Parties Bound. This Agreement shall be binding upon and inure to the
benefit of the parties hereto and their respective successors, assigns and legal
representatives; provided, however, that Borrower may not, without the prior
written consent of Lender, assign any rights, powers, duties, or obligations
hereunder.

     (i) Expenses. Borrower will promptly pay all reasonable costs, fees, and
expenses paid or incurred by Lender incident to this Agreement (including the
fees and expenses of counsel to Lender in connection with the negotiation,
preparation, and execution of this Agreement and any amendments hereto) or
incident to the collection of the Loan.

     (j) Headings. Section headings are for convenience of reference only and
shall in no way affect the interpretation of this Agreement.

     (k) Financial Terms. As used in this Agreement, all financial and
accounting terms not otherwise defined herein shall be defined and calculated in
accordance with generally accepted accounting principles consistently applied.

     (l) Counterparts. This Agreement may be executed in counterparts.

     THIS WRITTEN LOAN AGREEMENT REPRESENTS THE FINAL AGREEMENT BETWEEN THE
PARTIES REGARDING THE SUBJECT MATTER HEREOF AND MAY NOT BE CONTRADICTED BY
PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT ORAL AGREEMENT OF THE PARTIES. THERE ARE
NO UNWRITTEN ORAL AGREEMENTS BETWEEN THE PARTIES.

     If Borrower agrees to the foregoing, Borrower should execute this Agreement
in the spaces indicated on the signature page below.

                     REMAINDER OF PAGE INTENTIONALLY BLANK.
                          SIGNATURE PAGE(S) TO FOLLOW.


                                       9

<PAGE>   10

         Signature Page to the Loan Agreement dated as of the date first set
forth above, between Washington Oregon Wireless, LLC as Borrower, and Alamosa
Operations, Inc., as Lender.


                                    ALAMOSA OPERATIONS, INC.

                                    By:  /s/ David E. Sharbutt
                                         _____________________________
                                         Name: David E. Sharbutt
                                               _______________________
                                         Title: President


                                    Address:
                                    4403 Brownfield Highway
                                    Lubbock, Texas 79407
                                    Attention: President

                                    with copy to
                                    Haynes and Boone, LLP
                                    901 Main Street, Suite 3100
                                    Dallas, Texas 75202
                                    Attention: William S. Kleinman


AGREED AND ACCEPTED
as of July 31, 2000:


WASHINGTON OREGON WIRELESS, LLC


By: /s/ Mitchell Moore
    _______________________________________
    Mitchell Moore, Chief Executive Officer

Address:
5665 SW Meadows Road
Suite 100
Lake Oswego, Oregon 97035
Attention: Mitchell Moore, Chief Executive Officer




                 WASHINGTON OREGON WIRELESS, LLC LOAN AGREEMENT
                                 SIGNATURE PAGE



<PAGE>   11

                                    EXHIBIT A
                                  FORM OF NOTE

$11,000,000                                                        JULY __, 2000

         FOR VALUE RECEIVED, the undersigned, WASHINGTON OREGON WIRELESS, LLC
("BORROWER"), hereby promises to pay to the order of ALAMOSA OPERATIONS, INC.
("LENDER"), at Lender's principal office in Lubbock, Texas, on the Maturity Date
or, following the Merger Date, ON DEMAND, the lesser of (a) $11,000,000 or (b)
the aggregate principal disbursed by Lender to Borrower and outstanding and
unpaid on such date (together with accrued and unpaid interest thereon).

         This Note has been executed and delivered under, and is subject to the
terms of, the Loan Agreement, dated as of July _____, 2000 (as amended,
modified, supplemented, or restated from time to time, the "LOAN AGREEMENT"),
among Borrower and Lender, and is the "Note" referred to therein. Unless defined
herein, capitalized terms used herein that are defined in the Loan Agreement
have the meaning given to such terms in the Loan Agreement. Reference is made to
the Loan Agreement for provisions affecting this Note regarding applicable
interest rates, principal and interest payment dates, final maturity,
prepayments, acceleration of maturity, exercise of rights, subordination to
certain senior indebtedness, payment of attorneys' fees, court costs, and other
costs of collection, certain waivers by Borrower and others now or hereafter
obligated for payment of any sums due hereunder and security for the payment
hereof. Without limiting the immediately preceding sentence, reference is made
to SECTION 11(E) of the Loan Agreement for usury savings provisions.

         Borrower authorizes Lender and the holder of this Note to endorse on
the Schedule attached to this Note or any continuation thereof or to record in
their internal records all Advances made to Borrower hereunder and all payments
made on account of the principal thereof, which endorsements or recordings shall
be prima facie evidence as to the outstanding principal amount of this Note;
provided, however, any failure by Lender or the holder of this Note to make any
such endorsement or recording shall not limit or otherwise affect the
obligations of Borrower under the Loan Agreement, this Note, or any other Loan
Document.

         THIS NOTE AND THE OTHER LOAN DOCUMENTS HAVE BEEN ENTERED INTO PURSUANT
TO THE SUBSTANTIVE LAWS OF THE STATE OF TEXAS, AND THE APPLICABLE FEDERAL LAWS
OF THE UNITED STATES OF AMERICA SHALL GOVERN THE VALIDITY, CONSTRUCTION,
ENFORCEMENT, AND INTERPRETATION OF THIS NOTE.

                                     WASHINGTON OREGON WIRELESS, LLC
                                     an Oregon limited liability company


                                     By:
                                        ----------------------------------------
                                        Mitchell Moore, Chief Executive Officer


<PAGE>   12

                   SCHEDULE TO PROMISSORY NOTE IN THE ORIGINAL
                        PRINCIPAL AMOUNT OF $11,000,000,
                              DATED JULY ___, 2000,
                      EXECUTED BY WASHINGTON WIRELESS, LLC,
                       PAYABLE TO ALAMOSA OPERATIONS, INC.

--------------------------------------------------------------------------------
     DATE       AMOUNT OF ADVANCE      PRINCIPAL PAYMENT      PRINCIPAL BALANCE
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

                                       2
<PAGE>   13

                                    EXHIBIT B

                                FORM OF GUARANTY

         THIS GUARANTY (this "GUARANTY") is executed as of July ___, 2000, by
the undersigned ("GUARANTOR," whose address is set forth on the signature page
to this Guaranty, for the benefit of Alamosa Operations, Inc. ("LENDER"), whose
address is set forth on the signature page to this Guaranty.

                                 R E C I T A L S

         A. Washington Oregon Wireless, LLC and Lender have entered into a Loan
Agreement dated as of July ___, 2000 (as amended, modified, supplemented, or
restated from time to time, the "LOAN AGREEMENT").

         B. This Guaranty is integral to the transactions contemplated by the
Loan Agreement, and the execution and delivery hereof is a condition precedent
to the making of advances and other extensions of credit under the Loan
Agreement.

         ACCORDINGLY, for good and valuable consideration, the receipt and
adequacy of which are hereby acknowledged, Guarantor, agrees, for the benefit of
Lender, as follows:

1.       DEFINITIONS

         1.1 LOAN AGREEMENT DEFINITIONS. Unless otherwise defined herein, or the
context otherwise requires, terms used in this Guaranty, including its preamble
and recitals, have the meanings provided in the Loan Agreement.

         1.2 CERTAIN TERMS. The following terms when used in this Agreement,
including its preamble and recitals, have the following meanings (such
definitions to be equally applicable to the singular and plural forms thereof):

         BORROWER means Washington Oregon Wireless, LLC, an Oregon limited
liability company.

         GUARANTEED DEBT means all indebtedness, obligations, and liabilities of
Borrower to Lender arising under the Loan Agreement and the related Note.

2.       GUARANTY. Guarantor hereby irrevocably, unconditionally, and absolutely
guarantees in favor of Lender and its assigns the prompt payment when due of the
Guaranteed Debt if the Parent Merger is not consummated, provided, however, that
Guarantor's obligation to make payments to Lender hereunder shall be limited to
an amount equal to Guarantor's Pro Rata Portion (defined below) of the
Guaranteed Debt. As used herein, the term "PRO RATA PORTION" means a percentage
equal to the proportion that (a) Guarantor's total Capital Contribution
Commitment (defined below) bears to (b) the aggregate Capital Contribution
Commitments of all Members that have executed and delivered to Lender a Guaranty
in the form of EXHIBIT B to the Loan Agreement and all other Loan Documents
applicable to each such Member. As used herein, "CAPITAL CONTRIBUTION
COMMITMENT" means the amount (as set forth on SCHEDULE 6 to the Loan Agreement)
of obligations of each Member of Borrower to make capital contributions to
Borrower during the calendar year 2000. This is an unconditional guaranty of
payment, and not a guaranty of collection, and Lender may enforce Guarantor's
obligations hereunder without first suing, or enforcing its rights or remedies
against,


<PAGE>   14

Borrower or any other obligor, or enforcing or collecting any present or future
collateral security for any of the Guaranteed Debt. Lender may not enforce
Guarantor's obligations to make payments hereunder before October 1, 2000.

3.       CONSIDERATION. Guarantor represents and warrants that it has received
or will receive direct or indirect benefit from the making of this Guaranty and
the creation of the Guaranteed Debt, that Guarantor is familiar with the
financial condition of Borrower and the value of any collateral security, if
any, for the Guaranteed Debt and that Lender has made no representations to
Guarantor in order to induce Guarantor to execute this Guaranty.

3.       WAIVERS. Guarantor hereby waives notice of (a) acceptance of this
Guaranty, (b) the extension of credit by Lender to Borrower, (c) the occurrence
of any breach or default by Borrower in respect of the Guaranteed Debt, (d) the
sale or foreclosure on any collateral for any of the Guaranteed Debt, (e) the
transfer of all or any part of the Guaranteed Debt to any third party and (f)
all other notices including, but not limited to, notice of presentment, protest,
notice of protest, notice of non-payment, notice of intent to accelerate and
notice of acceleration with respect to all or any part of the Guaranteed Debt.
Further, Guarantor expressly waives each and every right to which it may be
entitled by virtue of the suretyship law of the state of Texas, including , but
not limited to, any rights pursuant to Rule 31, Texas Rules of Civil Procedure,
Articles 1986 and 1987, Revised Civil Statutes of Texas and Chapter 34 of the
Texas Business and Commerce Code.

4.       NO RELEASE. Guarantor hereby consents and agrees to, and acknowledges
that its obligations hereunder shall not be released or discharged by, the
following: (a) the renewal, extension, modification, or alteration of any Loan
Document, the Guaranteed Debt, or any related document or instrument; (b) any
forbearance or compromise granted to Borrower by Lender; (c) the insolvency,
bankruptcy, liquidation, or dissolution of Borrower or any other obligor (it is
specifically agreed, without limitation, that the filing of any bankruptcy or
similar proceeding by or against Borrower or any other obligor with respect to
any of the Guaranteed Debt shall not affect the obligations of Guarantor under
this Guaranty or the rights of Lender under this Guaranty, including, but not
limited to, the right or ability of Lender to pursue or institute suit against
Guarantor for the entire Guaranteed Debt; (d) the invalidity, illegality, or
unenforceability of all or any part of the Guaranteed Debt against Borrower or
any other obligor; (e) the full or partial release of Borrower or any other
obligor; (f) the release, surrender, exchange, subordination, deterioration,
waste, loss, or impairment (including, but not limited to, negligent, willful,
unreasonable, or unjustifiable impairment) of any collateral for any of the
Guaranteed Debt; (g) the failure of Lender to properly obtain, perfect, or
preserve any security interest or lien in any such collateral; (h) the failure
of Lender to exercise diligence, commercial reasonableness, or reasonable care
in the preservation, enforcement or sale of any such collateral (including, but
not limited to, the failure to conduct any foreclosure or other remedy fairly or
in such a way so as to obtain the best possible price or a favorable price or
otherwise act or fail to act); and (i) any other act or omission of Lender or
Borrower which would otherwise constitute or create a legal or equitable defense
in favor of Guarantor or increase the likelihood or risk that Guarantor will be
required to pay the Guaranteed Debt pursuant to the terms hereof.

5.       SUBROGATION AND CONTRIBUTION. Notwithstanding anything to the contrary
contained in this Guaranty, Guarantor waives all rights of subrogation,
reimbursement, indemnification, contribution, and all other claims against
Borrower and every other party which is or shall ever be in any way obligated on
the Guaranteed Debt which Guarantor may ever have as a result of payment of any
of the Guaranteed Debt, as well as all incidental rights and benefits in favor
of Guarantor in connection with payment of any of the Guaranteed Debt.

                                        2

<PAGE>   15

6.       SUBORDINATION. After default in the payment of any of the Guaranteed
Debt, Guarantor shall not receive or collect, directly or indirectly, from
Borrower or any other obligor, any payments on any debts and liabilities of
Borrower, or any distributions with respect to any ownership interest in
Borrower, to Guarantor, or any of them, whether now existing or hereafter
arising and whether direct, indirect, several, joint and several, or otherwise,
and howsoever evidenced or created (collectively, the "GUARANTOR CLAIMS"),
which, together with all liens, security interests, and all other encumbrances
or charges on assets securing the payment of all or any portion of the Guarantor
Claims, are hereby subordinated to, and are, and shall remain inferior and
subordinate to the Guaranteed Debt and all liens, security interests, and all
other encumbrances or charges on assets securing all or any portion of the
Guaranteed Debt.

7.       APPLICATION OF OTHER PAYMENTS. If Borrower is or shall hereafter be
liable to Lender for any obligation, indebtedness, or liability other than the
Guaranteed Debt, and Lender should collect or receive any payments, funds, or
distributions which are not specifically required, by law or agreement, to be
applied to the Guaranteed Debt, then Lender may, in its sole discretion, apply
such payments, funds, or distributions to indebtedness of Borrower other than
the Guaranteed Debt.

8.       INSOLVENCY OF GUARANTOR. The liability of Guarantor hereunder shall,
at the option of Lender, without notice, become immediately fixed and
enforceable for the full amount thereof, whether then due or not due, as though
all of the Guaranteed Debt had become past due if (i) Guarantor defaults in the
due performance of any term, covenant, or agreement contained in this Guaranty,
in the other Loan Documents, or otherwise in favor of Lender, or (ii) Guarantor
makes an assignment for the benefit of its creditors or a composition with
creditors, is unable or admits in writing its inability to pay, or generally
fails to pay, its debts as they mature, files a petition commencing a voluntary
case concerning Guarantor under any chapter of Title 11 of the United States
Code entitled "Bankruptcy"; or an involuntary case is commenced against
Guarantor under any such chapter and relief is ordered against it or the
petition is controverted but is not dismissed within 60 days after the
commencement of such case.

9.       BREACH BY GUARANTOR. If Guarantor breaches or fails to timely perform
any provisions of this Guaranty, Guarantor shall, immediately upon demand by
Lender, pay Lender all costs and expenses (including, but not limited to, court
costs and reasonable attorneys' fees) incurred by Lender in the enforcement
hereof or the preservation of Lender's rights hereunder. The covenant contained
in this PARAGRAPH 9 shall survive the payment of the Guaranteed Debt.

10.      ASSIGNS. This Guaranty shall be binding upon and inure to the benefit
of the parties hereto and their respective successors, assigns, and legal
representatives; provided, however, that Guarantor may not, without the prior
written consent of Lender, assign any of its rights, powers, duties, or
obligations hereunder.

11.      LOAN DOCUMENTS. This Guaranty is a Loan Document and is subject to the
applicable provisions of the Loan Agreement, all of which are incorporated into
this Guaranty by reference the same as if set forth in this Guaranty.

12.      TERMINATION. This Guaranty shall terminate and be of no further force
or effect on the Merger Date.

13.      MISCELLANEOUS. THIS GUARANTY REPRESENTS THE FINAL AGREEMENT BETWEEN THE
PARTIES REGARDING THE SUBJECT MATTER HEREOF AND MAY NOT BE CONTRADICTED BY
PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT ORAL AGREEMENT OF THE PARTIES. THERE ARE
NO UNWRITTEN ORAL AGREEMENTS BETWEEN THE PARTIES. This

                                        3
<PAGE>   16

Guaranty is given in addition to, and not in lieu of, any guaranty previously
given to Lender by Guarantor, and in no way impairs or limits Lender's other
rights and remedies against Guarantor. This Guaranty may be amended only by a
written instrument executed by Guarantor and Lender. The substantive laws of the
State of Texas shall govern the validity, construction, enforcement and
interpretation of this Guaranty. For purposes of litigation pertaining to this
Guaranty, Guarantor hereby irrevocably consents and submits to the non-exclusive
jurisdiction of state and federal courts located in the State of Texas.






                     REMAINDER OF PAGE INTENTIONALLY BLANK.
                          SIGNATURE PAGE(s) TO FOLLOW.

                                        4
<PAGE>   17

         EXECUTED as of the date first stated in this Guaranty.

Address:                                            GUARANTOR:


                                           By:                                 ,
----------------------------------             ---------------------------------
                                              Name:
----------------------------------                  ----------------------------
                                              Title:
----------------------------------                   ---------------------------


                                    GUARANTY
                                 SIGNATURE PAGE