555-1212 - Indexed lookup of telephone area code or country code.
555-1212.com's Fast Area Code Look-Up
American Computer Resources - Listing of international telephone country codes.
AmeriCom - Decode area code number or lookup code by city and state.
Area Code Finder - lists area codes for states and countries, either by number or by location.
Area Codes in Canada
Area Code Repair!
Area Code Splits.Com
CodeTel Dominican Republic
Complete U.S. Area Codes reference site - U.S. and territorial telephone area codes reference site maintained daily, with links to related information.
Fone Finder - Cross reference by area code and exchange to determine the TELCO and place name.
Internationale Telefon Vorwahlen
JCS Area Code Lookup - Search US Area Codes for Zip Code overlays, find all area codes for a state, and see area code changes by state or by year.
NANPA: North American Numbering Plan Administration
New Area Codes - from BellCore
Payphone Numbers
Telephone Area Code Finder - area code and time zone information for North America.
West Central Cellular - Texas