AllAreaCodes.com Online area code resource. This site was designed to allow you to find all the states, cities, and other areas serviced under the North American Numbering Plan.
Open Directory Project A large and comprehensive directory of web resources.
Switchboard.com A fast and easy way for people and businesses to find each other on the Web.
Telephone Directories on the Web Telephone and business directories from around the world.
United States Postal Service-ZIP Code Look-Up and Address Information Find a zip code for specific addresses, or find zip codes by city or region.