Here you have some Internet sites where you can compare budgets or arrange for rental cars. Most of them include the major companies (Hertz, Avis, Dollar, Alamo, National, Enterprise NYC, Thrifty, Advantage, Payless...) All links open a new window, so you can easily come back here.

4Airlines.com

Economy Travel

Quick and user friendly online booking engine. In their site clilck the "cars" icon for the rental car search engine.

They are one of the largest international ticket agencies. With a really great on-line booking engine, they offer car rentals starting at just $109 a week in Europe. In a couple of clicks you will surely find your car.
Also European hotels and airline tickets can be booked online.
Note: to be their customer you must have a credit card with a billing address in the United States.

Expedia.co.uk

An established and respected travel site. A really easy to use interface with an express search for flights, hotels, rental car agencies and holidays.
Note that Expedia.co.uk can only sell flights to customers with a UK delivery address

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