There are a bunch of different transportation options available.  Below are links to all the different ground transportation services available:

*Please note that you probably will not need a rental car if you are staying in the city.  You might want to see if your hotel offers a shuttle service from the airport*

Rental Car Options

Alamo Car Rental
Avis Car Rental
Budget Car Rental
Dollar Car Rental
Enterprise Car Rental
Hertz Car Rental
National Car Rental
Thrifty Car Rental

Car Service Options