js0610,
First let me welcome you to RR. I also live in Hays County, on the south side, near the Comal County line on 1102.
LCRA currently operates an EDACS 900 MHz trunking system, which is analog. Most of the older scanners will trunktrack an EDACS system in this band.
I have used a few older ones (Pro-2052, Pro-93, Pro-95, Pro-96, Pro-97) and currently use a PSR-500. You don't need anything special for this system, as long as it trunktracks an EDACS system, in the 900 MHz band.
In the future (they haven't said when yet) they're going to transition all of their public safety to a digital (P25) trunking system in the 700 MHz public safety band, and in fact they have already started the build out of this system (which is in the database as the LCRA-P25 system). I think this transition is still a ways off because all of the New Braunfels and San Marcos subscribers are still carrying analog radios.
If you have enough to spend on a new digital scanner it will receive analog and digital transmissions and would prevent you from having an obsolete scanner when LCRA does make the switch to their digital system.
Just start rattling off questions and we'll be glad to answer them.