I did build mine. Here are the stats.
Athlon 1.2GHz
Biostar mobo
512 PC2100 RAM
120GB HD
Hauppauge PVR-500MCE
IN win case
GeForce FX550 video card
Knoppmyth
Knoppmyth is really easy to set up. The only thing you have to watch for is tuner compatibility. My PVR 500 took some tweaking to get it to play nice.
I spent about a month reading and refining my hardware before putting it all together and another week or two making it all work how I wanted.
I've had it all running for a month or so now and it works great.