<PAGE>   1
                                                                   EXHIBIT 10.30

                           *Personal and Confidential*


                              EMPLOYMENT AGREEMENT

               between viaLINK INTERNATIONAL, Delaware corporation
                                   ("viaLink")

                                       and

                         WILLIAM CREASMAN, an individual
                                  ("Employee").

A.   Employee hereby accepts employment with viaLink for the position described
     on the attached Compensation Plan. The commencement date of the employment
     shall be as soon as practicable but in no event later than June 15, 2000
     (to be confirmed). This Employment Agreement shall also be subject to the
     Terms and Conditions of Employment attached hereto. Employee agrees that
     disputes arising from the employment will be subject to binding arbitration
     according to Section 7 of the Terms and Conditions. Employee acknowledges
     that Employee understands and agrees to said Terms and Conditions.

B.   Employee's annualized salary as set forth on the Compensation Plan shall be
     earned and payable bi-weekly, and subject to withholdings or other
     deductions required by law or otherwise authorized.

C.   Employee agrees and acknowledges that, notwithstanding anything in this
     Employment Agreement, the Compensation Plan, the Terms and Conditions, or
     in any other document, policy or practice of viaLink, Employee's employment
     is and shall remain AT WILL, and the employment may be terminated with or
     without cause at any time, for any reason or for no reason. No change in
     such AT WILL status shall be effective unless such change is in writing and
     executed by an authorized officer of viaLink.

D.   This Employment Agreement, the Compensation Plan, the Terms and Conditions
     of Employment and any other documents, if any, attached hereto constitute
     the entire agreement of the parties and supersedes all oral or written
     agreements or understandings between them regarding the subject matter
     hereof. No change, alteration or modification hereof may be made except in
     a writing signed by both parties to this Employment Agreement.

E.   viaLink's offer of employment as contained in this Employment Agreement
     expires and shall be deemed cancelled and revoked if not accepted by
     Employee, through Employee's signature hereon, by May 12, 2000 . This
     Employment Agreement shall only be effective if signed by both parties
     hereto.

viaLink International                     Employee

By: /s/ JAMES DAVIDSON                    /s/ WILLIAM P. CREASMAN
    -------------------------------       -------------------------------

Its: VP of Human Resources                Date: May 8, 2000
     ------------------------------             -------------------------

Date: 8/29/2000
      -----------------------------


<PAGE>   2


                           *Personal and Confidential*

                              viaLINK INTERNATIONAL
                       TERMS AND CONDITIONS OF EMPLOYMENT

1.       BENEFITS.

         1.1.     VACATION. Employee shall accrue vacation at the rate set forth
                  in the then current policy of viaLink relating thereto.

         1.2.     PROGRAMS. Employee shall be eligible for viaLink's group
                  benefits programs currently in place which are offered to all
                  employees of viaLink ("Programs"); provided, however, that
                  such Programs may be amended by viaLink from time to time in
                  its sole and absolute discretion. Eligibility for each of such
                  Programs shall be subject to and administered according to any
                  applicable documents relating to such Programs.

2.       EMPLOYEE DUTIES. Employee shall (i) perform all duties which are
         assigned to Employee by viaLink from time to time, (ii) devote his full
         time, attention, knowledge and skills during the normal business hours
         of vialink, as they may be established from time to time, in
         furtherance of the business of viaLink, and (iii) faithfully,
         diligently, and to the best of his ability, perform the duties
         described above and further viaLink's best interests.

3.       EMPLOYEE'S OBLIGATIONS, COVENANTS AND RESTRICTIONS.

         3.1.     RULES AND POLICIES. During the employment, Employee shall at
                  all times be subject to, observe and carry out such reasonable
                  rules, regulations, polices, directions and restrictions as
                  viaLink may from time to time establish, and those imposed by
                  law.

         3.2.     COMPANY PROPERTY. All papers, books and records of every kind
                  and description relating to the business and affairs of
                  viaLink, whether or not prepared by the Employee, shall be the
                  sole and exclusive property of viaLink, and the Employee shall
                  surrender them to viaLink at any time upon request. This
                  section shall survive the termination of the employment.

         3.3.     NON-COMPETITION. During the employment, Employee shall not
                  knowingly engage, and shall not knowingly solicit any
                  employees of viaLink or its subsidiaries or other affiliates
                  to engage in any commercial activities which are in any way in
                  competition with the activities of viaLink, or which in any
                  way materially interfere with the performance of Employee's
                  duties or responsibilities to viaLink.

         3.4.     CONFLICTS OF INTEREST. During the employment, Employee shall
                  not, directly or indirectly, alone or as a partner, officer,
                  director, employee, shareholder, consultant or agent of any
                  other corporation, partnership or other business organization,
                  be actively engaged in or concerned with any


                                                                   Initials: WPC
                                                                             ---
<PAGE>   3


                           *Personal and Confidential*

                  other duties or pursuits which materially interfere with the
                  performance of his duties as an Employee of viaLink. Without
                  limiting the generality of the foregoing, Employee shall
                  comply with any other conflict of interest policies which may
                  be adopted by viaLink from time to time.

         3.5.     MISAPPROPRIATION. Employee shall not knowingly acquire, use,
                  copy, or misappropriate any trade secret or proprietary
                  information belonging to any other company or person and shall
                  not cause, encourage or induce viaLink to acquire, use, copy,
                  or misappropriate any trade secret or proprietary information
                  belonging to any other company or person.

         3.6.     COMPLIANCE. Employee represents and warrants that Employee is
                  and shall at all times during the employment remain in
                  compliance with any and all applicable federal and/or state
                  laws, rules or regulations regarding Employee's eligibility
                  for employment and/or continued employment with viaLink.

         3.7.     NON-BREACH. Employee represents that by entering into the
                  employment, Employee is not in violation of any agreement,
                  term or condition of any other agreement Employee has had with
                  any third party, nor does the execution of the Employment
                  Agreement constitute a breach of any other agreement to which
                  Employee is a party.

4.       WORK PRODUCT.

         4.1.     Employee agrees that any and all inventions, improvements,
                  developments, discoveries, copyrightable works, or
                  contributions thereto, including, without limitation, any
                  written works, software products or code, images, designs,
                  and/or instructions, whether or not they are the subject of
                  patent or copyright or other proprietary rights protection
                  under any federal, state, local or foreign law(s), created in
                  whole or part by Employee during the term of this Agreement or
                  relating in any way to the business of viaLink (hereinafter
                  "Work Product") shall be the sole and exclusive property of
                  viaLink and shall belong to viaLink free and clear from all
                  right, title and interest of any other person, including,
                  without limiting the generality of the foregoing, Employee. It
                  is specifically agreed and understood that Employee shall not
                  retain any right, title, interest or any right to use any of
                  such Work Product. Employee shall promptly and fully disclose
                  to viaLink all such Work Product. Employee acknowledges that
                  all Work Product shall be a work for hire.

         4.2.     Employee conveys, transfers and assigns all rights, title and
                  interest in and to any Work Product to viaLink, and further
                  agrees to execute any written assignment or other agreement
                  viaLink deems necessary at any time to effect the foregoing
                  and to obtain or uphold, for viaLink's benefit, all copyright,
                  patent, and/or other rights of viaLink in such Work Product.


                                       2
                                                                   Initials: WPC
                                                                             ---
<PAGE>   4


                           *Personal and Confidential*

         4.3.     Employee's obligations in this Section 4 shall survive the
                  termination of this Agreement.

5.       TRADE SECRETS AND CONFIDENTIALITY.

         5.1.     CONFIDENTIAL INFORMATION. "Confidential Information" means
                  proprietary business information, Trade Secrets and/or other
                  confidential information regarding viaLink or any of its
                  subsidiaries which (i) have not otherwise become public
                  knowledge, (ii) were not already known to Employee or learned
                  by Employee from independent and unrestricted sources prior to
                  the Effective Date, and (iii) have not been disclosed by
                  viaLink to others without substantial restriction on further
                  disclosure. "Trade Secrets" means any proprietary information
                  not generally known in the industry in which viaLink is
                  engaged or may become engaged, including, without limitation,
                  information relating to viaLink's business affairs, finances,
                  properties, methods of operation, software developed by
                  viaLink, sources of and arrangements for hardware supplied to
                  clients of viaLink, submission and proposal procedures of
                  viaLink, viaLink's client or contact lists, commercial
                  information supplied to viaLink by viaLink's clients, and
                  other confidential information respecting the business or
                  affairs of viaLink. Employee acknowledges and agrees that the
                  business and good will of viaLink depend upon its keeping such
                  Confidential Information confidential.

         5.2.     NON-DISCLOSURE. Except when directed to do otherwise by the
                  President or Chief Executive Officer of viaLink, or any
                  successor to either of them, and except as required by law,
                  court order or subpoena, Employee shall keep confidential and
                  shall not divulge to any other person or entity, during the
                  term of this Agreement or at any time thereafter, any of
                  viaLink's Confidential Information. In any case where Employee
                  is compelled by law, court order or subpoena to disclose any
                  Confidential Information to any third person, Employee shall
                  advise viaLink in advance of such requirement and shall permit
                  viaLink to object, contest, intervene or obtain appropriate
                  protection of such information prior to its disclosure to any
                  person.

         5.3.     RETURN OF PROPERTY. Upon termination of this Agreement,
                  Employee and Employee's Personnel will turn over to viaLink
                  all documents, papers and other matter in the possession of or
                  under the control of Employee or Employee's Personnel that are
                  or relate to Confidential Information or Work Product.

         5.4.     INJUNCTIVE RELIEF. Employee acknowledges that disclosure of
                  any Confidential Information or Work Product by Employee will
                  give rise to irreparable injury, which is inadequately
                  compensable in damages, to viaLink or the owner of such
                  Confidential Information. Accordingly, viaLink or such other
                  party, in addition to any other remedies which are


                                       3
                                                                   Initials: WPC
                                                                             ---
<PAGE>   5


                           *Personal and Confidential*

                  elsewhere granted in this Agreement or which may be otherwise
                  available at law or in equity, may seek and obtain injunctive
                  relief against the breach or threatened breach of the
                  foregoing Section 5.2, any infringement upon any intellectual
                  property rights of viaLink, or any other breach of any term,
                  covenant, condition, warranty or representation of this
                  Agreement.

         5.5.     All obligations under this Section 5 shall survive the
                  termination of this Agreement.

6.       EMPLOYEE'S OBLIGATIONS AFTER EMPLOYMENT ENDS. Employee acknowledges and
         agrees that the obligations contained in this Section shall begin upon
         termination of employment.

         6.1.     For a period of two (2) years after cessation of Employee's
                  employment with viaLink for any reason (including termination
                  of employment by viaLink), Employee shall not, directly or
                  indirectly, alone, or as a partner, officer, director,
                  employee, shareholder, consultant or agent of any other
                  corporation, partnership or other business organization,
                  knowingly solicit the employment of, or hire, any employee of
                  viaLink, or any viaLink subsidiary, or cause any such employee
                  to terminate the employee's relationship with viaLink or any
                  viaLink subsidiary, without the prior written approval of
                  viaLink.

         6.2.     For a period of two (2) years after cessation of Employee's
                  employment with viaLink for any reason (including termination
                  of employment by viaLink), Employee shall not, directly or
                  indirectly, alone, or as a partner, officer, director,
                  employee, shareholder, consultant or agent of any other
                  corporation, partnership or other business organization,
                  knowingly solicit any of the accounts of viaLink which were
                  directly or indirectly serviced by the Employee unless such
                  solicitation is undertaken on behalf of a business venture
                  which does not compete, directly or indirectly, with the
                  products or services owned, sold, manufactured, marketed,
                  provided or developed by viaLink and its subsidiaries during
                  Employee's employment by viaLink. For the purposes of this
                  section, a business shall be deemed to be in competition with
                  viaLink and its subsidiaries if the products or services of
                  such business are substantially similar in purpose, function
                  or capability to the products or services then being
                  developed, manufactured, marketed, provided or sold by viaLink
                  or a viaLink subsidiary.

         6.3.     The parties agree that the any breach or threatened breach of
                  the provisions of this Section 6 will cause irreparable injury
                  to viaLink and that money damages will not provide an adequate
                  remedy. Accordingly, viaLink shall, in addition to other
                  remedies provided by law, be entitled to such equitable and
                  injunctive relief as may be necessary to enforce the
                  provisions of these Terms and Conditions against the Employee
                  or any person or entity participating in such breach or
                  threatened breach.
                                       4
                                                                   Initials: WPC
                                                                             ---
<PAGE>   6


                           *Personal and Confidential*

                  Nothing contained herein shall be construed as prohibiting
                  viaLink from pursuing any other and additional remedies
                  available to it, at law or in equity, for such breach or
                  threatened breach, including any recovery of damages from the
                  Employee and the immediate termination of the employment.


7.       RESOLUTION OF DISPUTES. Any controversy or claim arising out of or
         relating to the employment or termination thereof (including, without
         limitation, claims under Title VII of the Civil Rights Act of 1964, as
         amended, the Americans with Disabilities Act, and any other federal
         and/or state employment rights laws), and/or arising out of a
         controversy or claim regarding the Employment Agreement, these Terms
         and Conditions, the Programs, or any breach of any of the foregoing,
         and except for any claims for injunctive relief permitted by these
         Terms and Conditions, shall be settled by arbitration pursuant to the
         then current National Rules for the Resolution of Employment Disputes
         ("Rules") of the American Arbitration Association ("AAA"), subject to
         the following:

         7.1.     Within 15 days after the commencement of arbitration, each
                  party shall select one person to act as an arbitrator and the
                  two selected persons shall select a third arbitrator within 10
                  days of their appointment. If the arbitrators selected by the
                  parties are unable or fail to agree upon the third arbitrator,
                  the third arbitrator shall be selected by the American
                  Arbitration Association. All arbitrators selected shall be
                  persons having experience with and knowledge of the resolution
                  of employment-related disputes in the area in which the claim
                  or controversy arises.

         7.2.     The arbitration shall be conducted at the offices of viaLink
                  or such other location at which Employee is then or was most
                  recently employed by viaLink.

         7.3.     The arbitration shall be completed within six months of the
                  filing of the notice of intention to arbitrate (demand), and
                  the arbitrators shall agree to comply with this schedule
                  before accepting appointment. However, this time limit may be
                  extended by agreement of the parties.

         7.4.     Any arbitration award made shall not exceed the amount that
                  would have been available to the parties had the matter been
                  determined by litigation in a court of law.

         7.5.     The prevailing party shall be entitled to an award of all of
                  its reasonable costs incurred, including, without limitation,
                  reasonable attorneys' fees.

         7.6.     Except as may be required by law, neither a party nor an
                  arbitrator may disclose the existence, content, or results of
                  any arbitration hereunder without the prior written consent of
                  both parties.

         7.7.     Judgment upon any award rendered by the arbitrators may be
                  entered by any court having jurisdiction thereof.


                                       5
                                                                   Initials: WPC
                                                                             ---
<PAGE>   7

                           *Personal and Confidential*

8.       SUCCESSORS AND ASSIGNS. The rights and obligations of viaLink hereunder
         shall run in favor of and shall be binding upon viaLink, its
         successors, assigns, nominees or other legal representatives. Employee
         acknowledges that viaLink may assign its rights and obligations under
         the Employment Agreement without the consent of Employee. Employee may
         not assign his rights and obligations under the Employment Agreement.

9.       NOTICES. All notices, requests, demands and other communications
         hereunder must be in writing and shall be deemed to have been duly
         given upon receipt if delivered by hand, sent by telecopier or by
         courier, or three (3) days after such communication is mailed within
         the continental United States by first class certified mail, return
         receipt requested, postage prepaid, to the other party, in each case
         addressed as follows: (i) if to viaLink, to Human Resources, The
         viaLink Company, 13800 Benson Road Suite 100, Edmond, Oklahoma 73013
         and (ii) if to the Employee, to the last address shown for the Employee
         in the personnel records of viaLink. Addresses may be changed by
         written notice sent to the other party at the last recorded address of
         that party.

10.      SEVERABILITY. If any provision of the Employment shall be adjudged by
         any court of competent jurisdiction to be invalid or unenforceable for
         any reason, such judgment shall not affect, impair or invalidate the
         remainder of said terms and provisions.

11.      HEADINGS. The captions and headings in these Terms and Conditions are
         for convenience and reference only and shall not be construed as part
         of these Terms and Conditions or to limit or otherwise affect the
         meaning hereof.

12.      GOVERNING LAW. Jurisdiction over disputes with regard to the Employment
         Agreement and/or these Terms and Conditions shall be exclusively in the
         courts of the State of Delaware, and shall be construed in accordance
         with and governed by the laws of the state of Delaware.

13.      NONWAIVER. The waiver of any violation or breach of these Terms and
         Conditions by either party hereto shall not be deemed to be a waiver of
         any continuing violation or breach or a waiver of any other violation
         or breach of these Terms and Conditions.


                                       6
                                                                   Initials: WPC
                                                                             ---
<PAGE>   8


                           *Personal and Confidential*

                              VIALINK INTERNATIONAL
                                COMPENSATION PLAN
                                      FOR:
                                WILLIAM CREASMAN
                                   "Employee"

Salary:  The Annual Salary is earned and payable bi-weekly.

<TABLE>
<CAPTION>
  Employee's Position:                       Annual Salary:
  --------------------                       --------------
<S>                                          <C>
  Vice President                             $175,000
</TABLE>

  EMPLOYEE IS ELIGIBLE FOR THE ADDITIONAL COMPENSATION PROVISIONS BELOW.

[ ]      Performance Bonus:

  Beginning with the third quarter of 2000, Employee shall be eligible to
  receive an annual bonus equal to 50% of Employee's then current annual salary
  ("Bonus") if Employee satisfies the criteria established by viaLink's CEO
  ("Criteria"). Such Criteria for a given quarter shall be established by
  viaLink's CEO and communicated to Employee prior to the beginning of such
  quarter. Said Bonus shall accrue quarterly and shall be calculated and paid
  quarterly. Notwithstanding anything to the contrary in this Bonus provision,
  in order to receive a Bonus due hereunder, Employee must be an employee of
  viaLink under this Agreement at the end of a given quarter for which a bonus
  is earned pursuant to this provision. Any payment due for a quarter under this
  provision shall be paid not later than the next regular payroll after the
  sixtieth (60th) day following the end of each quarter for which any Bonus
  amount is earned.

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

[ ]      Stock Options:

  Subject to the conditions and restrictions ("Conditions and Restrictions")
  hereinafter set forth and subject to the terms, covenants and conditions of
  viaLink's 1999 Stock Option Plan ("Plan"), viaLink shall grant to Employee an
  option to purchase 35,000 shares of viaLink common stock at the grant price
  equal to the closing price of the viaLink common stock on the date of the
  actual grant of the options to Employee by viaLink. Such Conditions and
  Restrictions are as follows:

  o Employee must be an employee of viaLink on the actual date of said grant.

  o Employee must execute a Stock Option Agreement generally used by viaLink for
    the granting of stock options under said Plan. Such Stock Option Agreement
    shall include, but not limited to, the following terms and conditions:


                                       7
                                                                   Initials: WPC
                                                                             ---

<PAGE>   9


                           *Personal and Confidential*

    o The option rights shall vest in equal amounts over a three year period
      during the Term of the Employment Agreement; and

    o If Employee is terminated or the Employment Agreement is not renewed,
      whether with or without cause, or if said Agreement otherwise expires,
      except as may otherwise be provided in the change of control provisions in
      the Plan under which any options granted, Employee shall not be entitled
      to exercise any of such options which have not vested as of the date of
      such termination, non-renewal or earlier expiration of the Employment
      Agreement.


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


[ ] Severance:

  In the event that viaLink terminates the employment without cause at any time,
  Employee shall be entitled to severance compensation in an amount equal to six
  months of salary at Employee's salary rate at date of hire, payable over 12
  months.

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

[ ] Relocation:

  Employee shall be eligible for relocation reimbursement pursuant to the
  attached policy of viaLink regarding relocation expenses.

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


                                       8
                                                                   Initials: WPC
                                                                             ---
<PAGE>   10
                                  ATTACHMENT A

                              The viaLink Company
                       Relocation Reimbursement Agreement

    I hereby acknowledge that I have received and read a summary regarding
    benefits available to me under the Company relocation policy. I understand
    the benefits available and agree to the following:

1.  Any expenses that deviate from the policy must be approved in advance by the
    Vice President of Human Resources or his/her designee. If I should incur
    such an expense without prior approval, the Company may refuse to provide
    reimbursement, even though past practice has implied that the expense
    would/should have been reimbursed.

2.  Tax assistance will be paid on certain allowable items, which the Company
    believes are non-deductible (excluding the Relocation Allowance).

3.  The payment of my relocation expenses by the Company is conditional on my
    remaining in the employ of the Company for twelve (12) consecutive months
    after my effective start date with the Company, or my effective date of
    transfer into my new position (whichever may apply). If I should voluntarily
    resign from the Company or should my employment with the Company be
    terminated for cause prior to the completion of twelve (12) consecutive
    months after such date, I will repay to the Company all relocation
    reimbursement payments made to me or on my behalf, in accordance with the
    following schedule:

                     TERMINATION WITHIN           REPAYMENT
                     ------------------           ---------
                     1 - 12 months                 100%
                     After 1 year                    0

4.  Any repayment required under this agreement would be due and payable to the
    Company on the final working day of employment.

5.  If required, I authorize deductions to be withheld from my wages, salary,
    bonus, or other sums due me for any reason for any relocation expense
    amounts due the Company in accordance with the above schedule.

6.  Reimbursement or repayment of relocation expenses by the Company does not
    constitute a commitment by the Company with respect to the duration of
    employment.

/s/ WILLIAM P. CREASMAN                   William P. Creasman
--------------------------------          --------------------------------
Name (Signature)                          Name (Print)

Date: May 8, 2000
      --------------------------