um, well its pretty much impossible
it is not logical at all to build one, if you want to build the best route would be to get a barebone laptop and add your own parts
You can find an some Aopen barebones here http://www.chemusa.com/ they come with the videocard but the rest is pretty much up to you, you can find a lot of stuff for it on newegg
Are you talking about just barebones laptops? Yes it is certainly possible, and you will probably save a few hundred dollars, but the only hassle involved is if one of your parts fails, you will have to deal with the separate warranties, whereas if you bought it from a legit company you would get a comprehensive warranty covering everything.
im trying to build 1 also, except from what I understand, im alittle further along than you. www.mini-itx.comhttp://mini-itx.com on the left in most veiwed there is an itx lappy the only problem besides power(no battery,purpose destroy fact), which was his fault, is that it is big if you arent good at making cases with a dremel. i guess they make cases, but the point of his laptop was to have enough interior to be customized. hope this helps