Annual Reports Library - http://www.zpub.com/sf/arl/
Corporate reports for public companies, mutual funds, foundations, banks, and public institutions world wide, including samples that explain terms.
D&B Million Dollar Database - http://www.kcls.org/erout/goto.cfm?f=dbmillion&d=26
Directory information on 1 million+ U.S. companies with sales greater than $1 million and/or 20+ employees. Updated every 60 days.
How to Find U.S. Company Information - http://www.nypl.org/research/sibl/company/c2index.htm
New York Public Library's excellent guide to doing basic research on U.S. Companies. Includes print and CD-ROM materials, many of which are available in King County Library System, and internet sites.