Addresses, Phone Numbers, Zip Codes 

Switchboard Telephone Directories
Separate directories for over 90 million residential and 10 million commercial listings. Allows you to customize your own listing.

Area Decoder
Search for country and area codes for thousands of cities in the U.S. and abroad. Search by city or, conversely, by code.

GTE Superpages
More than 11 million business listings from over 5,000 Yellow Pages directories in the U. S. Search by business category or name, city and state, or telephone number. See alsoDirectory Assistance from AT&T. Internet 800 Directory
Directory of non-AT&T long distance numbers. Searchable by company name or by state.

Infobel
Fax, email, and phone directories for countries all over the world. Search in English, Spanish, French, Italian, Dutch and German.

ACR's International Calling Code Directory
Forget the country and city codes for Toulouse, France? Look no further. Alphabetical listing by country and city for thousands of locations worldwide, plus options for inexpensive online long distance phone calls.

United States Postal Service
Everything you ever wanted to know about the USPS but were afraid to ask. It includes: 5 and 9-digit zip codes for virtually all U.S. addresses, U.S. and International mailing rates, nifty stamp images, and more.

Franks's Compulsive Guide to Postal Addresses
Includes not only postal codes for countries of the world, but also conventions of addressing mail to these countries (with historical background!) See the country index.