It's just west of Bexar Co. (San Antonio's county). I think the hummers are more numerous on the coast, however. I'd like to go to the Rockport Hummingbird Festival sometime...I've seen these videos and I can't even imagine seeing that many at one time.
http://www.youtube.com/watch?v...
http://www.youtube.com/watch?v...
Oops, the second one was apparently in NE Texas!