3 links
How Stuff Works: Passport
howstuffworks.com
Explains when and why you need a passport, and offers tips on how to apply for one.
PassportInfo.Com
passportinfo.com
Provides a broad range of general information for Americans planning travel abroad, including passport information.
US State Department, Bureau of Consular Affairs
travel.state.gov
Consular services for United States citizens abroad. Visa services for foreigners, links to foreign consulates, visa fee tables and downloadable passport forms.