Alamo Rent A Car
1-800-327-9633
http://www.alamo.com

Auto Europe Car Rentals
Most listings are for Europe, however, car rentals in other countries are also available.
http://www.autoeurope.com

Avis
1-800-831-2847
The reservation section allows you make, change, confirm, or cancel reservations online
http://www.avis.com

BreezeNet's Guide to Airport Rental Cars
Click on your destination. Choose cities in the eastern or western US or go international. This site also has information for the under 25 driver.
http://www.bnm.com/rcar.htm

Dollar Rent A Car
1-800-800-4000
http://www.dollarcar.com

Enterprise Rent-A-Car
http://www.pickenterprise.com

Enterprise Rent A Car
1-800-566-9249,
http://www.pickenterprise.com/

Ford Rent A Car
http://www.ford.com/rentacar/

Hertz Rent A Car
1-800-654-3131
http://www.hertz.com

National Car Rental
1-800-227-7368
http://www.nationalcar.com

Rent-A-Wreck
Rent a gently used car, truck, or van. There are over 400 franchises around the world. Locate a franchise by state, city, or country.? Telephone numbers and addresses as well as some direct links to the various franchises are listed.
http://www.rent-a-wreck.com

Thrifty Car Rental
1-800-367-2277
http://www.thrifty.com

Yahoo! Travel
A very complete travel site.
http://travel.yahoo.com