I'm just really getting into the whole 'ham' radio idea and I'm looking at APRS or Automatic Packet Reporting System in the next radio. That gives you a good tracking process and can be used beyond just the car if you've got a portable. You can also patch together a fairly good version with your present smartphone or android device and a cheap 2 meter hand held radio.

Just thinking out side (or beyond) the box!

Paul -