We posted a story about someone doing some APRS tracking recently. This is old news to some, but new fresh stuff for others. If you want to build your own tracker, here’s a great writeup on one. The WhereAVR is low cost, low power and has plenty of I/O. With all of the schematics and PCB files available on his site, you should be able to get one working in quickly. He does need a little help building a nice simple configuration tool to work in windows, anyone want to volunteer?