<PAGE>

                                                                   EXHIBIT 3.112

                          CARDINAL BUSINESS MEDIA, INC.

                                     BY-LAWS

                                    ARTICLE I

                            MEETINGS OF STOCKHOLDERS

      Section 1. Place of Meeting and Notice. Meetings of the stockholders of
the Corporation shall be held at such place either within or without the State
of Delaware as the Board of Directors may determine.

      Section 2. Annual and Special Meetings. Annual meetings of stockholders
shall be held, at a date, time and place fixed by the Board of Directors and
stated in the notice of meeting, to elect a Board of Directors and to transact
such other business as may properly come before the meeting. Special meetings of
the stockholders may be called by the President for any purpose and shall be
called by the President or Secretary if directed by the Board of Directors or
requested in writing by the holders of not less than 25% of the capital stock of
the Corporation. Each such stockholder request shall state the purpose of the
proposed meeting.

      Section 3. Notice. Except as otherwise provided by law, at least 10 and
not more than 60 days before each meeting of stockholders, written notice of the
time, date and place of the meeting, and, in the case of a special meeting, the
purpose or purposes for which the meeting is called, shall be given to each
stockholder.

      Section 4. Quorum. At any meeting of stockholders, the holders of record,
present in person or by proxy, of a majority of the Corporation's issued and
outstanding capital stock shall constitute a quorum for the transaction of
business, except as otherwise provided by law. In the absence of a quorum, any
officer entitled to preside at or to act as secretary of the meeting shall have
power to adjourn the meeting from time to time until a quorum is present.

      Section 5. Voting. Except as otherwise provided by law, all matters
submitted to a meeting of stockholders shall be decided by vote of the holders
of record, present in person or by proxy, of a majority of the Corporation's
issued and outstanding capital stock.

                                   ARTICLE II

                                    DIRECTORS
<PAGE>

      Section 1. Number, Election and Removal of Directors. The number of
Directors that shall constitute the Board of Directors shall not be less than
one or more than fifteen. The first Board of Directors shall consist of three
Directors. Thereafter, within the limits specified above, the number of
Directors shall be determined by the Board of Directors or the stockholders. The
Directors shall be elected by stockholders at their annual meeting. Vacancies
and newly created directorships resulting from any increase in the number of
Directors may be filled by a majority of the Directors then in office, although
less than a quorum, or by the sole remaining Director or by the stockholders. A
Director may be removed with or without cause by the stockholders.

      Section 2. Meetings. Regular meetings of the Board of Directors shall be
held at such times and places as may from time to time be fixed by the Board of
Directors or as may be specified in a notice of meeting.

      Section 3. Quorum. One-third of the total number of Director shall
constitute a quorum for the transaction of business. If a quorum is not present
at any meeting of the Board of Directors, the Directors present may adjourn the
meeting from time to time, without notice other than announcement at the
meeting, until such a quorum is present. Except as otherwise provided by law,
the Certificate of Incorporation of the Corporation, these By-Laws or any
contract or agreement to which the Corporation is a party, the act of a majority
of the Directors present at any meeting at which there is a quorum shall be the
act of the Board of Directors.

      Section 4. Committees. The Board of Directors may, by resolution adopted
by a majority of the whole Board, designate one or more committees, including,
without limitation, an Executive Committee, to have and exercise such power and
authority as the Board of Directors shall specify. In the absence or
disqualification of a member of a committee, the member or members thereof
present at any meeting and not disqualified from voting, whether or not he or
they constitute a quorum, may unanimously appoint another Director to act at the
meeting in place of any such absent or disqualified member.

                                   ARTICLE III

                                    OFFICERS

      The officers of the Corporation shall consist of a President, a Secretary,
a Treasurer and such other additional officers with such titles as the Board of
Directors shall determine, all of which shall be chosen by and shall serve at
the pleasure of the Board of Directors. Such officers shall have the usual
powers and shall perform all the usual duties incident to their respective
offices. All officers shall be subject to the supervision and direction of the
Board of Directors. The authority, duties or responsibilities of any officer of
the Corporation may be suspended by the President with or without cause. Any
officer elected or appointed by the Board of Directors may be removed by the
Board of Directors with or without cause.
<PAGE>

                                   ARTICLE IV

                                 INDEMNIFICATION

      To the fullest extent permitted by the Delaware General Corporation Law,
the Corporation shall indemnify any current or former Director or officer of the
Corporation and may, at the discretion of the Board of Directors, indemnify any
current or former employee or agent of the Corporation against all expenses,
judgments, fines and amounts paid in settlement actually and reasonably incurred
by him in connection with any threatened, pending or completed action, suit or
proceeding brought by or in the right of the Corporation or otherwise, to which
he was or is a party by reason of his current or former position with the
Corporation or by reason of the fact that he is or was serving, at the request
of the Corporation, as a director, officer, partner, trustee, employee or agent
of another corporation, partnership, joint venture, trust or other enterprise.

                                    ARTICLE V

                               GENERAL PROVISIONS

      Section 1. Notices. Whenever any statute, the Certificate of Incorporation
or these By-Laws require notice to be given to any Director or stockholder, such
notice may be given in writing by mail, addressed to such Director or
stockholder at his address as it appears in the records of the Corporation, with
postage thereon prepaid. Such notice shall be deemed to have been given when it
is deposited in the United States mail. Notice to Directors may also be given by
telegram.

      Section 2. Fiscal Year. The fiscal year of the Corporation shall be fixed
by the Board of Directors