q6600, asus p5q pro, and an asus 4850. there are probably better options mb-wise, but it's been adequate. this is probably my 3rd build. mechanically it's all pretty simple - the hardest things are probably the heat sink and thermal paste and wire management. the heat sink/thermal paste is obviously a lot easier or harder depending on which one you get, but still take your time there and do it right, especially if you're oc'ing. there are thousands of heatsink reviews out there, so it is important to pick a good one, but you don't really have to spend more than 35-40 on it. wire management is obviously not difficult, but takes some foresight.

are you oc'ing? make sure you get the right version of the q6600 - there are 2 different ones and one's a lot better for oc. i forget how to tell.