I don't think its really possible to build a laptop. im not really sure why, I dont know if it has to do with the keyboard/mouse or whatever.
if you really wanted to practice before building you could probly go to a computer shop and get some old celeron based machine for 20 bucks, take it apart and put it back togather.
even memory now is so cheap I see you don't have to worry about skimping. I always get crucial memory and its 100 bucks for 2 gigs.
Just looking quick on new egg its still about 600 bucks to build a sick machine(that price seems constant, just the specs get better over time), then depends what you want to spend on a case. The only thing is i think i might wait until the 3.0ghz duo 2s come down to the less than 200 range. 180-200 always seems to be the deal area for bang for the buck cpu wise. duo core 2 3ghz has to be absurdly fast.
the most important thing is to get a cool case
