If you are looking for businesses by name or type of business, visit these yellow page web sites:

Switchboard.com http://switchboard.com
AnyWho http://www.anywho.com
Reference
USA
Search this databases of over 12 million companies by name, yellow page listing,
location and more. Search results also include contact name, estimated sales,
number of employees and credit ratings.
Thomas
Register http://thomasregister.com
This directory of U.S. and Canadian manufacturers can be searched by company
name, product, or brand name. Registration required.
Hoovers http://www.hoovers.com
Features company capsules, news, officers, financials and industry
information.
These sources may offer additional information about businesses:
Better
Business Bureau http://www.bbb.org
Search for business reliability reports at the sites of local
Better Business Bureaus.
Chambers
of Commerce http://www.uschamber.org/Chambers/Chamber+Directory/default.htm
Local chambers of commerce are excellent sources of information about companies
in their area.Use this database to find chambers in a given location.
Secretaries
of State http://www.internet-prospector.org/secstate.html
If a business has been incorporated, it is done through the
office of the Secretary of State in the state in which the incorporation
occurred. This site provides contact information and links to official
Secretary of State, and Corporation Databases (when available) for all
U.S. States.
New
York Department of State Corporation/Business Entity Database
http://wdb.dos.state.ny.us/corp_public/corp_wdb.corp_search_inputs.show
Search for New York State corporations, not-for-profits and business
entities. Provides address and filing date.