Man sorry to see this. When I was in Texas a few years back a next door neighbor had his older Vett's wheels jacked. At least they left his on cinder blocks. Seeing my S on rocks would set me off. I know others have mentioned the law in TX (god i love my home state) and I don't know about the laws were you are but heres another item for around $150 that could be used in conjunction with that silent alarm...
http://www.impactguns.com/store/752334345103.html
Doesn't look pretty but it gets the job done. Cheapest new pistol I've ever seen and not a bad shot. A friends got one and you can get it in .45, 40 S&W, or 9mm. His is a 40 S&W and its a good reliable home defense gun for him, even though the most he needs home defense from here in the middle of the corn rows is coyotes. Good luck with the car man, sorry again to see what happened.