411.com offers white and yellow page lookups, area and zip code lookups, and reverse searches for phone numbers addresses.
Anywho provides nationwide telephone directory listings, area code look-ups, reverse searches from phone numbers to the owners, and a toll-free number search.
Escape Artist provides dialing codes for calling other countries, directory service, links to embassies, conversion services, maps, and electrical voltage for travelers.
gethuman offers hope to people who dont want to deal with phone trees when trying to contact customer services at companies nationwide. gethuman lists companies and methods for circumventing their phone trees.
Infobel offers links to telephone directory services worldwide.
Internet 800 Directory
Internet 800 Directory searches for toll-free numbers nationwide.
PeopleFinder offers free searches for telephone numbers and addresses including reverse searches.
PhoneNumber.com offers searching for phone numbers, area codes and zip codes, and reverse searches by address and phone number.
Postal Codes for Other Countries
EmbassyWorld provides postal codes for other countries.
Switchboard.com provides access to telephone directory listings.
Try Zabasearch for telephone and address searches.
Zip Code Search
The United States Postal Service offers this Zip Code search service.