<PAGE>   1
                                                                    EXHIBIT 10.6


<TABLE>
<S>                             <C>                 <C>                    <C>
                                               BORROWER

                                SECOND LINE, INC.

      FIRSTATE BANK
       11210 HURON                                                          VARIABLE RATE
NORTHGLENN, COLORADO 80234                      ADDRESS                      COMMERCIAL
     (303) 451-1010                                                        PROMISSORY NOTE
        "LENDER"               5555 W. EVANS AVE.
                               DENVER, CO 80227

                               TELEPHONE NO.        IDENTIFICATION NO.
</TABLE>

<TABLE>
<CAPTION>
    OFFICER      INTEREST         PRINCIPAL        FUNDING        MATURITY          CUSTOMER           LOAN
   INITIALS        RATE            AMOUNT           DATE            DATE             NUMBER           NUMBER
---------------------------------------------------------------------------------------------------------------
<S>              <C>            <C>               <C>            <C>                <C>             <C>
      GP         VARIABLE       $912,976.00       09/17/97        09/15/02                            152062
---------------------------------------------------------------------------------------------------------------
</TABLE>

                                 PROMISE TO PAY

For value received, Borrower promises to pay to the order of Lender indicated
above the principal amount of NINE HUNDRED TWELVE THOUSAND NINE HUNDRED
SEVENTY-SIX AND NO/100 Dollars ($912,976.00) plus interest on the unpaid
principal balance at the rate and in the manner described below. All amounts
received by Lender shall be applied first to late payment charges and expenses,
then to accrued interest, and then to principal.

INTEREST RATE: This Note has a variable interest rate feature. Interest on the
Note may change from time to time if the Index Rate identified below changes.
Interest shall be computed on the basis of 360 days and the actual number of
days per year. Interest on this Note shall be calculated at a variable rate
equal to ONE AND 750/1000 percent (1.750%) per annum over the Index Rate. The
initial Index Rate is EIGHT AND 500/1000 percent (8.5%) per annum. Therefore,
the initial interest rate on this Note shall be TEN AND 250/1000 percent
(10.250%) per annum. Any change in the interest rate resulting from a change in
the Index Rate will be effective on:
ANNIVERSARY DATE OF THE NOTE

INDEX RATE: The Index Rate for this Note shall be: PRIME RATE AS PUBLISHED IN
THE WALL STREET JOURNAL

MINIMUM RATE/MAXIMUM RATE: The minimum interest rate on this Note shall be n/a
percent (n/a%) per annum. The maximum interest rate on this Note shall not
exceed TWENTY-ONE AND NO/1000 percent (21.000%) per annum or the maximum
interest rate Lender is permitted to charge by law, whichever is less.

DEFAULT RATE: In the event of any default under this Note, the Lender may in its
discretion, determine that all amounts owed to Lender shall bear interest at the
lesser of: N/A, or the maximum interest rate Lender is permitted to charge by
law.

PAYMENT SCHEDULE: Borrower shall pay the principal and interest according to the
following schedule:

         59 PAYMENTS OF $8,276.76 BEGINNING OCTOBER 15, 1997 AND CONTINUING AT
         MONTHLY TIME INTERVALS THEREAFTER. A FINAL PAYMENT OF THE UNPAID
         PRINCIPAL BALANCE PLUS ACCRUED INTEREST IS DUE AND PAYABLE ON
         SEPTEMBER 15, 2002.

All payments will be made to Lender at its address described above and in lawful
currency of the United States of America.


<PAGE>   2


RENEWAL:  If checked, [ ] this Note is a renewal of Loan Number _______________.

SECURITY: To secure the payment and performance of obligations incurred under
this Note, Borrower grants Lender a security interest in, and pledges and
assigns to Lender all of Borrower's rights, title, and interest, in all monies,
instruments, savings, checking and other deposit accounts of Borrower's,
(excluding IRA, Keogh and trust accounts and deposits subject to tax penalties
if so assigned) that are now or in the future in Lender's custody or control.
Upon default, and to the extent permitted by applicable law, Lender may exercise
its security interest in all such property which shall be in addition to
Lender's common law right of setoff. [X] If checked, the obligations under this
Note are also secured by a lien and/or security interest in the property
described in the documents executed in connection with this Note as well as any
other property designated as security now or in the future.

PREPAYMENT: This Note may be prepaid in part or in full on or before its
maturity date. If this Note contains more than one installment, all prepayments
will be credited as determined by Lender and as permitted by law. If this Note
is prepaid in full, there will be: [X] No minimum finance charge or prepayment
penalty. [ ] A minimum finance charge of $__________. [ ] A prepayment penalty
of ______% of the principal prepaid.

LATE PAYMENT CHARGE: If a payment is received more than N/A days late, Borrower
will be charged a late payment charge of $ n/a or n/a % of the payment amount,
whichever is [ ] greater [ ] less, as permitted by law.

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

BORROWER ACKNOWLEDGES THAT BORROWER HAS READ, UNDERSTANDS, AND AGREES TO THE
TERMS AND CONDITIONS OF THIS NOTE INCLUDING THE PROVISIONS ON THE REVERSE SIDE.
BORROWER ACKNOWLEDGES RECEIPT OF AN EXACT COPY OF THIS NOTE.

NOTE DATE: SEPTEMBER 17, 1997

BORROWER: SECOND LINE, INC.              BORROWER:

/s/ Thomas Higginson
---------------------------------        ---------------------------------
THOMAS HIGGINSON
PRESIDENT

BORROWER:                                BORROWER:

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


BORROWER:                                BORROWER:

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


BORROWER:                                BORROWER:

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


<PAGE>   3


                              TERMS AND CONDITIONS

1. DEFAULT. Borrower will be in default under this Note in the event that
Borrower or any guarantor:

         (a)      fails to make any payment on this Note or any other
                  indebtedness to Lender when due;

         (b)      fails to perform any obligation or breaches any warranty or
                  covenant to Lender contained in this Note or any other present
                  or future written agreement regarding this or any indebtedness
                  of Borrower to Lender;

         (c)      provides or causes any false or misleading signature or
                  representation to be provided to Lender;

         (d)      allows the collateral securing this Note (if any) to be lost,
                  stolen, destroyed, damaged in any material respect, or
                  subjected to seizure or confiscation;

         (e)      permits the entry or service of any garnishment, judgment, tax
                  levy, attachment or lien against Borrower, any guarantor, or
                  any of their property;

         (f)      dies, becomes legally incompetent, is dissolved or terminated,
                  ceases to operate its business, becomes insolvent, makes an
                  assignment for the benefit of creditors, or becomes the
                  subject of any bankruptcy, insolvency or debtor rehabilitation
                  proceeding; or

         (g)      causes Lender to deem itself insecure for any reason, or
                  Lender, for any reason, in good faith deems itself insecure.

2. RIGHTS OF LENDER ON DEFAULT. If there is a default under this Note, Lender
will be entitled to exercise one or more of the following remedies without
notice or demand (except as required by law):

         (a)      to declare the principal amount plus accrued interest under
                  this Note and all other present and future obligations of
                  Borrower immediately due and payable in full;

         (b)      to collect the outstanding obligations of Borrower with or
                  without resorting to judicial process;

         (c)      to take possession of any collateral in any manner permitted
                  by law;

         (d)      to require Borrower to deliver and make available to Lender
                  any collateral at a place reasonably convenient to Borrower
                  and Lender;

         (e)      to sell, lease or otherwise dispose of any collateral and
                  collect any deficiency balance with or without resorting to
                  legal process;

         (f)      to set-off Borrower's obligations against any amounts due to
                  Borrower including, but not limited to monies, instruments,
                  and deposit accounts maintained with Lender; and

         (g)      to exercise all other rights available to Lender under any
                  other written agreement or applicable law.

Lender's rights are cumulative and may be exercised together, separately, and in
any order. Lender's remedies under this paragraph are in addition to those
available at common law, such as the right of set-off.

3. DEMAND FEATURE: If this Note contains a demand feature, then notwithstanding
anything to the contrary contained in this Note, Lender's rights with respect to
the events of default identified above shall not be limited, restricted,
impaired or otherwise adversely affected by the demand feature of this Note.
Lender's rights to demand payment, at any time, and from time to time, shall be
in Lender's sole and absolute discretion, whether or not any default has
occurred.

<PAGE>   4


4. FINANCIAL INFORMATION: Borrower will provide Lender with current financial
statements and other financial information (including, but not limited to,
balance sheets and profit and loss statements) upon request.

5. MODIFICATION AND WAIVER: The modification or waiver of any of Borrower's
obligations or Lender's rights under this Note must be contained in a writing
signed by Lender. Lender may perform any of Borrower's obligations or delay or
fail to exercise any of its rights without causing a waiver of those obligations
or rights. A waiver on one occasion will not constitute a waiver on any other
occasion. Borrower's obligations under this Note shall not be affected if Lender
amends, compromises, exchanges, fails to exercise, impairs or releases any of
the obligations belonging to any co-borrower or guarantor or any of its rights
against any co-borrower, guarantor or collateral.

6. SEVERABILITY AND INTEREST LIMITATION: If any provision of this Note violates
the law or is unenforceable, the rest of the Note will remain valid.
Notwithstanding anything contained in this Note to the contrary, in no event
shall interest accrue under this Note, before or after maturity, at a rate in
excess of the highest rate permitted by applicable law, and if interest
(including any charge or fee held to be interest by a court of competent
jurisdiction) in excess thereof be paid, any excess shall constitute a payment
of, and be applied to, the principal balance hereof, and if the principal
balance has been fully paid, then such interest shall be prepaid to the
Borrower.

7. ASSIGNMENT: Borrower will not be entitled to assign any of its rights,
remedies or obligations described in this Note without the prior written consent
of Lender which may be withheld by Lender in its sole discretion. Lender will be
entitled to assign some or all of its rights and remedies described in this Note
without notice to or the prior consent of Borrower in any manner.

8. NOTICE: Any notice or other communication to be provided to Borrower or
Lender under this Note shall be in writing and sent to the parties at the
addresses described in this Note or such other address as the parties may
designate in writing from time to time.

9. APPLICABLE LAW: This Note shall be governed by the laws of the state
indicated in Lender's address. Borrower consents to the jurisdiction and venue
of any court located in the state indicated in Lender's address in the event of
any legal proceeding pertaining to the negotiation, execution, performance or
enforcement of any term or condition contained in this Note or any related loan
document and agrees not to commence or seek to remove such legal proceeding in
or to a different court.

10. COLLECTION COSTS: If Lender hires an attorney to assist in collecting any
amount due or enforcing any right or remedy under this Note, Borrower agrees to
pay Lender's attorney's fees, to the extent permitted by applicable law, and
collection costs.

11. MISCELLANEOUS: This Note is being executed for commercial/agricultural
purposes. Borrower and Lender agree that time is of the essence. Borrower waives
presentment, demand for payment, notice of dishonor and protest. BORROWER HEREBY
WAIVES ANY RIGHT TO TRIAL BY JURY IN ANY CIVIL ACTION ARISING OUT OF, OR BASED
UPON, THIS NOTE OR THE COLLATERAL SECURING THIS NOTE. If Lender obtains a
judgment for any amount due under this Note, interest will accrue on the
judgment at the Default Rate described in this Note. All references to Borrower
in this Note shall include all of the parties signing this Note. If there is
more than one Borrower, their obligations will be joint and several. This Note
and any related documents represent the complete and integrated understanding
between Borrower and Lender pertaining to the terms and conditions of those
documents.

12. ADDITIONAL TERMS:


LPCOMTC(C)FormAtion Technologies, Inc. (11/14/91) (800) 937-3799

<PAGE>   5


FIRSTATE BANK OF COLORADO

11210 HURON STREET
NORTHGLENN, CO 80234
(303) 451-1010
"LENDER"

                              COMMERCIAL CONTINUING
                                    GUARANTY

<TABLE>
<CAPTION>
         GUARANTOR                                        BORROWER

<S>                            <C>                        <C>                    <C>
         DAVID ALTOMARE                                   SECOND LINE, INC.

         ADDRESS                                          ADDRESS

                                                          5555 W. EVANS AVENUE
                                                          DENVER CO 80227

         TELEPHONE NO.         IDENTIFICATION NO.         TELEPHONE NO.          IDENTIFICATION NO.
</TABLE>

         1. CONSIDERATION. This Guaranty is being executed to induce Lender
indicated above to enter into one or more loans or other financial
accommodations with or on behalf of Borrower.

         2. GUARANTY. Guarantor hereby unconditionally guarantees the prompt and
full payment and performance of Borrower's present and future, joint and/or
several, direct and indirect, absolute and contingent, express and implied,
indebtedness, liabilities, obligations and covenants (cumulatively
"Obligations") to Lender as follows:

[X]      UNLIMITED: Guarantor's Obligations under this Guaranty shall be
         unlimited and shall include all present or future Obligations between
         Borrower and Lender (whether executed for the same or different
         purposes than the foregoing), together with all interest end all of
         Lender's expenses and costs, incurred in connection with the
         Obligations, including any amendments, extensions, modifications,
         renewals, replacements or substitutions thereto.

[ ]      LIMITED: Guarantor's Obligations under this Guaranty shall include all
         present or future written agreements between Borrower and Lender
         (whether executed for the same or different purposes), but shall be
         limited to the principal amount of ____________________________________
         _______________________________________________________________________
         Dollars, together with all interest end all of Lender's expenses and
         costs, incurred in connection with the Obligation, including any
         amendments, extensions, modifications, renewals, replacements or
         substitutions thereto.

[ ]      LIMITED TO THE FOLLOWING DESCRIBED NOTES/AGREEMENTS: Guarantor's
         Obligations under this Guaranty shall be limited to the following
         described promissory notes and agreements between Borrower and Lender,
         together with all interest and all of Lender's expenses and costs,
         incurred in connection with the Obligations, including any amendments,
         extensions, modifications, renewals, replacements or substitutions
         thereto:

<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------------------------
  INTEREST      PRINCIPAL AMOUNT/        FUNDING/         MATURITY        CUSTOMER             LOAN
    RATE           CREDIT LIMIT          AGREEMENT          DATE           NUMBER             NUMBER
                                           DATE
------------------------------------------------------------------------------------------------------------
<S>             <C>                      <C>              <C>             <C>                 <C>


------------------------------------------------------------------------------------------------------------
</TABLE>

<PAGE>   6


         3. ABSOLUTE AND CONTINUING NATURE OF GUARANTY. Guarantor's obligations
under this Guaranty are absolute and continuing and shall not be affected or
impaired if Lender amends, renews, extends, compromises, exchanges, falls to
exercise, impairs or releases any of the obligations belonging to any Borrower,
Co-guarantor or third party or any of Lender's rights against any Borrower,
Go-guarantor, third party, or collateral. In addition, Guarantor's Obligations
under this Guaranty shall not be affected or impaired by the death,
incompetency, termination, dissolution, insolvency, business cessation, or other
financial deterioration of any Borrower, Guarantor, or third party.

         4. DIRECT AND UNCONDITIONAL NATURE OF GUARANTY. Guarantor's Obligations
under this Guaranty are direct and unconditional and may be enforced without
requiring Lender to exercise, enforce, or exhaust any right or remedy against
any Borrower, Co-guarantor, third party, or collateral.

         5. WAIVER OF NOTICE. Guarantor hereby waives notice of the acceptance
of this Guaranty; notice of present and future extensions of credit and other
financial accommodations by Lender to any Borrower; notice of presentment for
payment, demand, protest, dishonor, default, and nonpayment pertaining to the
Obligations and this Guaranty and all other notices and demands pertaining to
the Obligations and this Guaranty as permitted by law.

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

GUARANTOR ACKNOWLEDGES GUARANTOR HAS READ, UNDERSTANDS, AND AGREES TO THE TERMS
AND CONDITIONS OF THIS AGREEMENT INCLUDING THE TERMS AND CONDITIONS ON THE
REVERSE SIDE. GUARANTOR HAS EXECUTED THIS AGREEMENT WITH THE INTENT TO BE
LEGALLY BOUND. GUARANTOR ACKNOWLEDGES RECEIPT OF AN EXACT COPY OF THIS
AGREEMENT.

DATED: SEPTEMBER 17, 1997

GUARANTOR: DAVID ALTOMARE                GUARANTOR:



/s/ David Altomare
-----------------------------------      -----------------------------------
DAVID ALTOMARE


GUARANTOR:                               GUARANTOR:


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