Directories and Phone Books

Allareacodes.com -- All area codes
Anywho.com -- focuses on providing telephone directory information for individuals and companies worldwide
Askart.com/askart/index.aspx -- "The artists’ blue book." Provides information on thousands of American artists and related links to museums, auction houses, and more
Gpoaccess.gov/cdirectory/index.html -- Congressional Directory
Health.usnews.com/health/best-hospitals/search -- Hospital Directory
Inter800.com -- Internet 800 Directory
Martindale.com -- Martindale Lawyer Locator
Superpages.com -- Provides phone directory lookup services. Searches yellow, white pages, maps and reverse phone book directories
Switchboard.com -- Provides phone directory lookup services. Searches yellow, white pages, maps and reverse phone book directories
Thomasnet.com -- Manufacturers, distributers, and service providers