Links to local business journals, including D.C and Baltimore, and a searchable archive of publications.
Some areas require a free registration.
This link takes you to the Fortune site. Click on the Fortune 500 link on the left. This site provides links to company home pages, detailed reports from the Securities and Exchange Commission, and newpaper articles and stock prices, both current and historic. Most useful for finding historical stock information, including prices by date back to 1985. Not all stocks are covered.