If you're doing private company research and don't have the money for a monthly membership with a business information provider, like Lexis-Nexis or Hoover's, search around for a provider that will sell business information by the download. You can buy reports direct from Dun & Bradstreet or one its resellers. Many resellers will also show you a sample company report first via PDF, to make sure you understand before buying what kind of information you will be getting. You can get similar by-the-download information from Marketresearch.com. which charges hundreds or even thousands of dollars for a report. Industry-specific sites, like Forrester or Jupiter in the Internet/Tech sector, also make reports available by the download.
Not sure what to expect from a full company analysis report, or not sure if it's worth the cash? A company like Manta.com will sell sample company reports from D&B and other information providers one at a time with fees starting at $9.95 for a list of business contacts, to $129.95 for a comprehensive D&B report.