well, i searched high and low, read all the stuff here for a few weeks, thought about P4 vs. VIA, build my own, etc. and finally just very simply ended up here:
http://www.upont.com/latte.asp. I plan on mounting it in the glove box, and should receive it this week. At the site above, under 'Accessories' is where the car adapter is listed.
Thoughts?