Galveston Island (near Houston), Corpus Christi & South Padre Island are beach areas...
Austin is the state capital w/ landmarks, scenery (rivers, lakes, canyons, hills, wildlife!), UTexas, Johnson Presidential Library, museums, etc. Austin is generally the central spot for people touring TX. Waco & Crawford TX are 45mins north of Austin; location of Baylor Univ. & relatively close to the President's ranch. San Marcos is 45mins south of Austin, location of alot of outlet malls/shopping, underground caverns/springs. Budha is 30miles east of Austin, new shopping plaza & recreational area are under development; animal safari is also planned.
Houston is the largest city in TX. Johnson Space Center, 6-Flags Astro-World, museums, restaurants, Galleria, int'l foods & shopping, professional sports (Basketball: Rockets, Football: Texans), Rice Univeristy & George Herbert Walker Bush Presidential Library, Kemho boardwalk. There are two airports, Hoby & Bush Intercontinental. Houston is approximately 175 miles south-east of Austin. About a hour and a half to the north is Lake Charles, Louisiana where there are many casino's.
Dallas is also a large city w/ fine dining & shopping, ranches, zoo/acquarium, professional sports (Basketball: Mavericks, Hockey: Stars, Football: Cowboys), art galleries, etc. There are two airports, Love Field & Dallas-Ft Worth. Dallas is approx. 175 miles north of Austin.
San Antonio is the 2nd largest city in Texas w/ alot of diversity. Scenic landmarks such as the Alamo, Hemisphere tower, and Riverwalk are worthwhile seeing. There's also a Sea World & 6-Flags Fiesta. This year, the New Orleans Saints are playing some of their home games in the Alamo-dome. San Antonio is approx. 90 miles south from Austin.
Brownsville is a border city en'route to Mexico. Ditto for Laredo. About 4-5hr drives from Austin (I think?).
El Paso is very unique, about 10 hrs west of Austin. Very cliche` Ol' Western movies-like. Famous river, Rio Grande. Authentic mexican/spanish food at it's bests, from my experiences!