Here are some reliable starting points for finding information on private corporations!

• Forbes.com -- Click on "Lists" then scroll down. On the right screen click on "Companies" to view best small, large & private companies
• Better Business Bureau -- for consumer & business reviews, reports, ratings, complaints, etc.
• Fortune 500 Lists-- annual lists of top 500 corporations, based on revenue
  • Historical Lists -- from 1955 to last year
  • Current List -- the latest year
  • Best Lists
• Hoover's Online Company Information
     Portions of corporation information are available in Nexis Uni
• ThomasNet -- Formerly Thomas Register; directory of companies, their products & services