Well there are a few good ones down here. However, they aren't always open to the public. Here are the names, they post events on their websites typically within about a week of the event. Watch them and if they have one just head on over to them, buy a glass for $5 and get 3 free pints.
My favorite two are:
512 Brewing (Excellent IPA, they also have a good pecan porter, and cream stout)
And
Jester King (Wytchmaker Rye is good, Awesome brewery campus)
There are also:
Uncle Billys (its a brew pub, so you can visit it and eat anytime)
Live Oak
Independence
Real Ale (Blanco, not far)
St Arnolds (Houston)
Also here are a few beer bars that have some of the draughts from these breweries: