TRANSPORTATION
George Bush Intercontinental Airport
Bush Intercontinental Airport (IAH), the 8th busiest commercial airport in the US, joined the Houston Airport System in June 1969. It is located approximately 23 miles north of downtown Houston, near the Sam Houston Tollway (Beltway 8 North).
http://iah.houstonairportsystem.org/
William P. Hobby Airport
Houston's second largest airport, Hobby Airport (HOU), has been serving the Houston for more than 60 years. Hobby Airport is located approximately seven miles south of downtown Houston, near I-45/Gulf Freeway, the major highway heading from the City to NASA and Galveston Island. Hobby Airport is the 41st busiest airport in the nation.
http://hou.houstonairportsystem.org/
GROUND TRANSPORTATION SERVICES  
Taxi, bus, and other ground transportation services are available from these airports to Houston and the surrounding area.
Standard Taxi Rates (from Bush Int'l): $33.50 (North Houston) or $37.50 (Downtown/CBD) to $73.50 (Nasa Space Center).
http://iah.houstonairportsystem.org/transportation
Rental Cars:
Rent-A-Car Advantage 800-777-5500, Alamo 800-327-9633, Avis 800-331-1212, Hertz 800-654-3131.
Travel Information Centers of the Texas, Department of Transportation, offers trip routing information and emergency road conditions. 800 452 9292 (8 a.m. and 5 p.m. daily).

PUBLIC TRANSPORTATION
The Metropolitan Transit Authority of Harris County, known as METRO, is a comprehensive plan that features a variety of transportation solutions for METRO's 1,285-square-mile service area: 72 miles of rail, a all encompassing bus service and more than 250 miles of two-way, all-day Park & Ride service.
http://www.ridemetro.org/homepage.asp