Thread: Basic cheap carputer to run xbmc

Right I'm new to building my own computer so I apologise If what I ask is dumb.
I need a list of parts (as cheap as possible) to build a carputer that will soley run xbmc live. Iv read that xbmc can be booted as the operating system so as to keep the need for a high performance system low. As well as running xbmc I would need it to be able to use a 4 wire USB touch screen. Could some one run down a parts list to accomplish this please. I already have the 4 wire USB touch screen and the power supply would need to be 12volt because it's in the car