I finally found a free front end for my carPC that I really like.  Since I built the PC I've been using a front end called MediaCar to play music and videos.  Unfortunately though, MediaCar is old and no longer supported.

So I got a new front end called RoadRunner that I really like.  It's constantly updated/patched and highly supported by the carPC community.  It's got hundreds of different skins that you can download and use with it, plus it supports music and video playback, Internet, external apps, GPS, phone, and radio.  Obviously, you'll need some additional hardware to get items like the radio, or phone to work.

But with this new front end, I'm now going to try to get the GPS working.  First thing I need, a GPS receiver.  They're fairly cheap and easily plug right into your PC's USB port.  Then I'll need to purchase some GPS software/maps.  The Road Runner developers say iGuidance or Destinator are good GPS programs that embed into their front end quite well.  So we'll see.