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                                                                     EXHIBIT 4.9



                                 FIRST AMENDMENT


         FIRST AMENDMENT (this "Amendment"), dated as of October 29, 1999, among
INFOUSA INC., a Delaware Corporation (the "Borrower"), the lenders party to the
Credit Agreement referred to below (the "Lenders"), and BANKERS TRUST COMPANY,
as Administrative Agent (the "Administrative Agent"). All capitalized terms used
herein and not otherwise defined shall have the respective meanings provided
such terms in the Credit Agreement referred to below.

                              W I T N E S S E T H:

         WHEREAS, the Borrower, the Lenders and the Administrative Agent are
parties to a Credit Agreement, dated as of July 23, 1999 (the "Credit
Agreement"); and

         WHEREAS, the parties hereto wish to amend the Credit Agreement as
herein provided, subject to and on the terms and conditions set forth herein;

         NOW, THEREFORE, it is agreed:

         1. Section 7.25 of the Credit Agreement is hereby amended by deleting
the date "October 31, 1999" appearing therein and inserting the date "November
30, 1999" in lieu thereof.

         2. Section 8.13 of the Credit Agreement is hereby amended by deleting
the date "October 31, 1999" appearing therein and inserting the date "November
30, 1999" in lieu thereof.

         3. In order to induce the Lenders to enter into this Amendment, the
Borrower hereby represents and warrants that (i) the representations, warranties
and agreements contained in Section 7 of the Credit Agreement are true and
correct in all material respects on and as of the First Amendment Effective Date
(as defined in Section 7 of this Amendment) and after giving effect to this
Amendment (it being understood and agreed that any representation or warranty
which by its terms is made as of a specified date shall be required to be true
and correct in all material respects only as of such specified date), and (ii)
there exists no Default or Event of Default on the First Amendment Effective
Date after giving effect to this Amendment.

         4. This Amendment is limited as specified and shall not constitute a
modification, acceptance or waiver of any other provision of the Credit
Agreement or any other Credit Document.

         5. This Amendment may be executed in any number of counterparts and by
the different parties hereto on separate counterparts, each of which
counterparts when executed and delivered shall be an original, but all of which
shall together constitute one and the same instrument. A complete set of
counterparts shall be lodged with the Borrower and the Administrative Agent.


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         6. THIS AMENDMENT AND THE RIGHTS AND OBLIGATIONS OF THE PARTIES
HEREUNDER SHALL BE CONSTRUED IN ACCORDANCE WITH AND GOVERNED BY THE LAW OF THE
STATE OF NEW YORK.

         7. This Amendment shall become effective on the date (the "First
Amendment Effective Date") when the Borrower and the Required Lenders shall have
signed a counterpart hereof (whether the same or different counterparts) and
shall have delivered (including by way of facsimile transmission) the same to
the Administrative Agent at the Notice Office.

         8. From and after the First Amendment Effective Date, all references in
the Credit Agreement and each of the Credit Documents to the Credit Agreement
shall be deemed to be references to the Credit Agreement as amended hereby.


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         IN WITNESS WHEREOF, each of the parties hereto has caused a counterpart
of this amendment to be duly executed and delivered as of the date first above
written.


                                  INFOUSA INC.

                                  By: /s/ JACK J. MCGOVERN
                                      ------------------------------------------
                                      Name:  Jack J. McGovern
                                      Title: Chief Financial Officer


                                  BANKERS TRUST COMPANY,
                                  Individually and as Administrative Agent

                                  By: /s/ DAVID J. BELL
                                      ------------------------------------------
                                      Name:  David J. Bell
                                      Title: Principal


                                  US BANK NATIONAL ASSOCIATION

                                  By: /s/ KEVIN D. MUNRO
                                      ------------------------------------------
                                      Name:  Kevin D. Munro
                                      Title: Vice President


                                  UNION BANK OF CALIFORNIA, N.A.

                                  By: /s/ HAGOP V. JAZMADARIAN
                                      ------------------------------------------
                                      Name:  Hagop V. Jazmadarian
                                      Title: Vice President


                                  [AND OTHER PARTICIPATING LENDERS]



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                                SECOND AMENDMENT


         SECOND AMENDMENT (this "Amendment"), dated as of December 15, 1999,
among INFOUSA INC., a Delaware corporation (the "Borrower"), the lenders party
to the Credit Agreement referred to below (the "Lenders"), and BANKERS TRUST
COMPANY, as Administrative Agent (the "Administrative Agent"). All capitalized
terms used herein and not otherwise defined shall have the respective meanings
provided such terms in the Credit Agreement referred to below.

                              W I T N E S S E T H:

         WHEREAS, the Borrower, the Lenders and the Administrative Agent are
parties to a Credit Agreement, dated as of July 23, 1999 (as amended, modified
or supplemented through, but not including, the date hereof, the "Credit
Agreement");

         WHEREAS, the Borrower has requested the Lenders to treat, and the
Lenders have agreed to treat, infoUSA.com Inc., currently a Wholly-Owned
Domestic Subsidiary of the Borrower, as an Unrestricted Subsidiary under (and as
defined in) the Credit Agreement (after giving effect to this Amendment) on the
terms and conditions set forth herein; and

         WHEREAS, the parties hereto wish to amend the Credit Agreement as
herein provided, subject to and on the terms and conditions set forth herein;

         NOW, THEREFORE, it is agreed:

         1. Section 4.02(e) of the Credit Agreement is hereby amended by
deleting the first parenthetical appearing in the first proviso thereof and
inserting the following new parenthetical in lieu thereof:


     "(other than cash proceeds received by the Borrower or any of its
     Subsidiaries from the sale of the InfoSpace Stock or the capital
     stock of any Unrestricted Subsidiary, which cash proceeds (in
     either case) shall be applied as provided above in this Section
     4.02(e) without regard to this proviso)".


         2. Section 8 of the Credit Agreement is hereby amended by inserting the
following new Sections 8.20 and 8.21 at the end thereof:

            "8.20 Ownership in info.com. The Borrower and/or a Subsidiary
     Guarantor will at all times maintain an equity ownership interest
     (on a fully diluted basis) in the capital stock of info.com equal
     to at least 35% of the total outstanding capital stock of
     info.com (on a fully diluted basis).

            8.21 Corporate Separateness. The Borrower will take, and will
     cause each of its Subsidiaries and Unrestricted Subsidiaries to
     take, all action as is necessary to keep the operations of the
     Borrower and its Subsidiaries separate and apart from those of
     any Unrestricted Subsidiary including, without limitation,



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     ensuring that all customary formalities regarding their
     respective corporate existence, including holding regular board
     of directors' and shareholders' meetings and maintenance of
     corporate offices and records, are followed. Neither the Borrower
     nor any of its Subsidiaries will make any payment to a creditor
     of any Unrestricted Subsidiary in respect of any liability of any
     Unrestricted Subsidiary. All financial statements provided to
     creditors shall clearly evidence the corporate separateness of
     the Borrower and its Subsidiaries from any Unrestricted
     Subsidiary, and the Borrower and its Subsidiaries will maintain
     their own respective payroll and separate books of account and
     bank accounts from Unrestricted Subsidiaries. Each Unrestricted
     Subsidiary will pay its respective liabilities, including all
     administrative expenses, from its own separate assets, and assets
     of the Borrower and its Subsidiaries will at all times be
     separately identified and segregated from the assets of
     Unrestricted Subsidiaries. Finally, neither the Borrower nor any
     of its Subsidiaries or Unrestricted Subsidiaries will take any
     action, or conduct its affairs in a manner which is likely to
     result in the corporate existence of any Unrestricted Subsidiary
     being ignored, or in the assets and liabilities of any
     Unrestricted Subsidiary being substantively consolidated with
     those of the Borrower or any of its Subsidiaries in a bankruptcy,
     reorganization or other insolvency proceeding."

         3. Section 9.02 of the Credit Agreement is hereby amended by (i)
inserting the text "and each of the Borrower and its Subsidiaries may license
intellectual property to the Unrestricted Subsidiaries in an arms-length
transaction" at the end of clause (ii) thereof, (ii) deleting the word "and"
appearing at the end of clause (xii) thereof, (iii) deleting the period
appearing at the end of clause (xiii) thereof and inserting "; and" in lieu
thereof and (iv) inserting the following new clause (xiv) at the end thereof:

            "(xiv) the Borrower and/or a Subsidiary Guarantor may sell shares
     of the capital stock of Unrestricted Subsidiaries so long as (i)
     no Default or no Event of Default then exists or would result
     therefrom (including under Section 8.20), (ii) each such sale is
     in an arm's-length transaction and the Borrower or such
     Subsidiary Guarantor receives at least fair market value (as
     determined in good faith by the Borrower), (iii) the total
     consideration received by the Borrower or such Subsidiary
     Guarantor is 100% cash and is paid at the time of the closing of
     such sale and (iv) the Net Sale Proceeds therefrom are applied as
     required by Section 4.02(e)."

         4. Section 9.11(a) of the Credit Agreement is hereby amended by (i)
deleting the word "or" appearing at the end of clause (iii) thereof, (ii)
deleting the period appearing at the end of clause (iv) thereof and inserting ";
or" in lieu thereof and (iii) inserting the following new clause (v) at the end
thereof:

            "(v) amend, modify or change the Unrestricted Subsidiary Tax
     Sharing Agreement without the prior written consent of the
     Administrative Agent."

         5. Section 10 of the Credit Agreement is hereby amended by (i) deleting
the word "or" appearing at the end of Section 10.09 thereof, (iii) inserting the
word "or" at the ending


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of Section 10.10 thereof and (iii) inserting the following new Section 10.11
immediately after such Section 10.10:

            "10.11 Unrestricted Subsidiary Tax Payments. Any Unrestricted
     Subsidiary shall not pay any material amounts owing by it under
     the Unrestricted Subsidiary Tax Sharing Agreement and such
     failure shall continue unremedied for 30 or more days;".

         6. The definition of "Consolidated Net Income" appearing in Section 11
of the Credit Agreement is hereby amended by inserting the parenthetical
"(including each Unrestricted Subsidiary)" after the phrase "the net income of
any other Person which is not a Subsidiary of the Borrower" appearing in clause
(i) of the proviso thereof.

         7. The definition of "Subsidiary" appearing in Section 11 of the Credit
Agreement is hereby amended by inserting the following new sentence at the end
of such definition:

            "Notwithstanding the foregoing (and except for purposes of the
     definition of Unrestricted Subsidiary contained herein), an
     Unrestricted Subsidiary shall be deemed not to be a Subsidiary of
     the Borrower or any of its other Subsidiaries for purposes of
     this Agreement."

         8. Section 11 of the Credit Agreement is hereby further amended by
inserting the following new definitions in their appropriate alphabetical order:

            "info.com" shall mean infoUSA.com Inc., a Delaware corporation.

            "Unrestricted Subsidiary" shall mean info.com and any Subsidiary
     of info.com, provided that info.com and its Subsidiaries shall
     only be permitted as Unrestricted Subsidiaries so long as (I) no
     such Unrestricted Subsidiary owns any capital stock of, or other
     equity interests in, or has any Lien on any property of, the
     Borrower or any Subsidiary of the Borrower other than a
     Subsidiary of an Unrestricted Subsidiary, and (II) any
     Indebtedness and other obligations of such Unrestricted
     Subsidiaries are non-recourse to the Borrower or any of its other
     Subsidiaries

            "Unrestricted Subsidiary Tax Sharing Agreement" shall mean a tax
     sharing agreement entered into by the Borrower and info.com."

         9. Section 13.07(a) of the Credit Agreement is hereby amended by (i)
inserting "(i)" immediately after the words "provided that," appearing therein
and (ii) inserting the following text at the end of the proviso contained
therein:

            "and (ii) the financial results of Unrestricted Subsidiaries
     shall be ignored".


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         10. In order to induce the Lenders to enter into this Amendment, the
Borrower hereby represents and warrants that (i) the representations, warranties
and agreements contained in Section 7 of the Credit Agreement are true and
correct in all material respects on and as of the Second Amendment Effective
Date (as defined in Section 16 of this Amendment), both before and after giving
effect to this Amendment (it being understood and agreed that any representation
or warranty which by its terms is made as of a specified date shall be required
to be true and correct in all material respects only as of such specified date),
(ii) there exists no Default or Event of Default on the Second Amendment
Effective Date, both before and after giving effect to this Amendment, and (iii)
info.com is permitted to be designated as an "Unrestricted Subsidiary" for
purposes of, and as defined in, the Senior Subordinated Note Indenture.

         11. Upon the occurrence of the Second Amendment Effective Date, the
Lenders hereby agree that infoUSA.com Inc. shall be released from all of its
obligations under the Credit Documents to which it is a party.

         12. In order to induce the Lenders to enter into this Amendment, the
Borrower hereby agrees to pay to each Lender which executes and delivers to the
Administrative Agent a counterpart of this Amendment on or before 5:00 p.m. (New
York time) on December 21, 1999, a fee equal to .05% of the sum of (I) such
Lender's Revolving Loan Commitment on the Second Amendment Effective Date and
(II) the aggregate outstanding principal amount of such Lender's Term Loans on
the Second Amendment Effective Date, with such fee to be earned on the Second
Amendment Effective Date and payable on the Business Day immediately thereafter.

         13. This Amendment is limited as specified and shall not constitute a
modification, acceptance or waiver of any other provision of the Credit
Agreement or any other Credit Document.

         14. This Amendment may be executed in any number of counterparts and by
the different parties hereto on separate counterparts, each of which
counterparts when executed and delivered shall be an original, but all of which
shall together constitute one and the same instrument. A complete set of
counterparts shall be lodged with the Borrower and the Administrative Agent.

         15. THIS AMENDMENT AND THE RIGHTS AND OBLIGATIONS OF THE PARTIES
HEREUNDER SHALL BE CONSTRUED IN ACCORDANCE WITH AND GOVERNED BY THE LAW OF THE
STATE OF NEW YORK.

         16. This Amendment shall become effective on the date (the "Second
Amendment Effective Date") when (i) the Borrower and the Required Lenders shall
have signed a counterpart hereof (whether the same or different counterparts)
and shall have delivered (including by way of facsimile transmission) the same
to the Administrative Agent at the Notice Office and (ii) the Unrestricted
Subsidiary Tax Sharing Agreement shall have been entered into on terms and
conditions satisfactory to the Administrative Agent.

         17. From and after the Second Amendment Effective Date, all references
in the Credit Agreement and each of the Credit Documents to the Credit Agreement
shall be deemed to be references to the Credit Agreement as amended hereby.

                                      * * *


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         IN WITNESS WHEREOF, each of the parties hereto has caused a counterpart
of this Amendment to be duly executed and delivered as of the date first above
written.


                                    INFOUSA INC.

                                    By: /s/ STORMY L. DEAN
                                        ----------------------------------------
                                        Name:  Stormy L. Dean
                                        Title: Vice President and Treasurer


                                    BANKERS TRUST COMPANY,
                                    Individually and as Administrative Agent

                                    By: /s/ DAVID J. BELL
                                        ----------------------------------------
                                        Name:  David J. Bell
                                        Title: Principal


                                    US BANK NATIONAL ASSOCIATION

                                    By: /s/ KEVIN D. MUNRO
                                        ----------------------------------------
                                        Name:  Kevin D. Munro
                                        Title: Vice President


                                    UNION BANK OF CALIFORNIA, N.A.

                                    By: /s/ HAGOP V. JAZMADARIAN
                                        ----------------------------------------
                                        Name:  Hagop V. Jazmadarian
                                        Title: Vice President


                                    [AND OTHER PARTICIPATING LENDERS]


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