APRS
Lots of info
Some notes on available hardware
Argent Data Systems
Products for amateur radio including APRS applications
2m Transmitter MX146 from SRB -- This is a 500 mW transmitter, $70
OpenTracker+ is open source / open hardware and uses a Motorola MCU.
Tracker2
These are controllers, connects a data stream (eg weather or gps) to a Kantronics TNC.
They now have a Tracker2 with a 5 watt 2m radio now. T2-301 $229
Byonics
Maker of TinyTrak controllers and MicroTrak transmitters
20 Aug 2010
I just bought a couple. I got a TinyTrak4 controller kit to use with my 2m HT and a MicroTrak MT8000 10 watt transmitter to use on my bicycle.
Updates will go here when the parts arrive.
TinyTrak4
Information from the source: http://www.byonics.com/tinytrak4/
The wiki: http://www.vk7hse.hobby-site.org/wiki/index.php/Main_Page
Setting up an iGate
Sam Buchanan's notes: http://www.vansairforce.com/community/showthread.php?t=30180