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                                                                     EXHIBIT 4.2

                                FOURTH AMENDMENT

                  FOURTH AMENDMENT (this "Amendment"), dated as of June 8, 2000,
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, VideoYellowPagesUSA.com, Inc. ("VYP"),
businessCreditUSA.com, Inc. ("BC") and ListBazaar.com, Inc. ("LB"), each
currently a Wholly-Owned Domestic Subsidiary of the Borrower, as additional
Unrestricted Subsidiaries 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 8.20 of the Credit Agreement is hereby deleted and
the following new Section 8.20 is inserted in lieu thereof:

                  "8.20 Ownership in Unrestricted Subsidiaries. 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
         each of info.com, VYP, BC and LB equal to at least 35% of the total
         outstanding capital stock of each such Unrestricted Subsidiary (on a
         fully diluted basis)."

                  2. Section 9.05 of the Credit Agreement is hereby amended by
(i) deleting the word "and" appearing at the end of clause (xv) thereof, (ii)
deleting the period appearing at the end of clause (xvi) thereof and inserting
"; and" in lieu thereof and (iii) inserting the following new clause (xvii) at
the end thereof:

                  "(xvii) the Borrower may contribute the assets of its
         businessCreditUSA.com operating unit to BC."


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                  3. Clause (v) of Section 9.11(a) of the Credit Agreement is
hereby deleted and the following new clause (v) is inserted in lieu thereof:

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

                  4. Section 10.11 of the Credit Agreement is hereby deleted and
the following new Section 10.11 is inserted in lieu thereof:

                  "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 to which it is a party
         and such failure shall continue unremedied for 30 or more days;".

                  5. The definitions of "Unrestricted Subsidiary" and
"Unrestricted Subsidiary Tax Sharing Agreement" appearing in Section 11 of the
Credit Agreement are hereby deleted and the following new definitions of
"Unrestricted Subsidiary" and "Unrestricted Subsidiary Tax Sharing Agreement"
are inserted in lieu thereof:

                  "Unrestricted Subsidiary" shall mean each of info.com, VYP, BC
         and LB and each of their respective Subsidiaries provided that each
         such Person 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
         each tax sharing agreement entered into by the Borrower and an
         Unrestricted Subsidiary.

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

                  "BC" shall mean businessCreditUSA.com, Inc., a Delaware
         corporation.

                  "LB" shall mean ListBazaar.com, Inc., a Delaware corporation.

                  "VYP" shall mean VideoYellowPagesUSA.com, Inc., a Delaware
         corporation.

                  7. 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 Fourth
Amendment Effective Date (as defined in Section 13 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


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Event of Default on the Fourth Amendment Effective Date, both before and after
giving effect to this Amendment, and (iii) each of VYP, BC and LB is permitted
to be designated as an "Unrestricted Subsidiary" for purposes of, and as defined
in, the Senior Subordinated Note Indenture.

                  8. Upon the occurrence of the Fourth Amendment Effective Date,
the Lenders hereby agree that each of VYP, BC and LB shall be released from all
of its obligations under the Credit Documents to which it is a party and all
liens on their assets also shall be released from the Security Documents.

                  9. 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 June 21, 2000, a fee equal to .05% of the
sum of (I) such Lender's Revolving Loan Commitment on the Fourth Amendment
Effective Date and (II) the aggregate outstanding principal amount of such
Lender's Term Loans on the Fourth Amendment Effective Date, with such fee to be
earned on the Fourth Amendment Effective Date and payable on the Business Day
immediately thereafter.

                  10. 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.

                  11. 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.

                  12. 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.

                  13. This Amendment shall become effective on the date (the
"Fourth 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 Agreements with VYP, BC and LB shall
have been entered into on terms and conditions satisfactory to the
Administrative Agent.

                  14. From and after the Fourth 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: 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]