I built a Window Forms version to display information from a GPS. Haven't really touched it much since, but if you are interested the code is on CodePlex.
http://gps.codeplex.com/SourceControl/changeset/view/24953#146657
All that you need to do to get this tracking somebody is
- Convert to Windows Mobile
- Build a Web Service for recording location
- Modify code to post location to Web Service every so often
Really I already did the hard work, or parsing the GPS commands from the serial connection for you. :)