gps tracking

Hey does anyone know anything about GPS tracking devices? I want to get something in my new ride incase its stolen. I found this on ebay:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=130145148215&ssPageName=STRK:MEWA:IT&ih=003

I wonder how well this is gonna work?

Since that system uses a phone, there is a much cheaper way to accomplish the same thing, without service fees.

What you is take an old cell phone (which can be accurately tracked via the phone’s service provider) and attach it to the underside of the dash in a hidden spot. This phone need not be activated for this to work. Since 911 calls are always functional from unactivated phones, and the phone company can track it to within tens of feet, it just need to be on when you are not in the car.
Using the SN of the phone you can call the phone’s servie provider (in conjunction with the police) and have the phone (and car) tracked. Basically you wire it in so the phone stays on and charged, that way if a thief happens to snip the wires charging the phone, it’ll still function for a few more hours. It’s pretty much free, and works well…several documented cases on H-T and T-I.

You’ll need a system that can’t be easily disable or even found right way.

http://www.gpshunter.com/US/HP60AMPS.htm

http://www.autotechs.com/items/item1770.htm

I just want MagnaVolt!