Fortune magazine lets you view their database of information using a variety of categories. This site also features the Business Web Site Directory with links to over 60,000 web sites owned and operated by businesses all over the world. A huge database of companies and investment information. The feature here is Hoover's searchable directory of thousands of U S and foreign companies, public and private, which provides financials and contact information as well links to company websites and current stock price. This service can be used to identify businesses by type and size for any geographic area.
Many employers have links to their homepages where employment opportunities are listed.
You can browse their directory looking for companies alphabetically or use the search engine database. A great way to look for companies with homepages. Or, check out Fortune , Your Company , and others. The index is full-text WAIS index of the header information contained in each document. You can enter your own query in the search dialog.