previous post was edited.
also, i wouldnt worry about lapping your heatsink unless you either just want to do it for the hell of it, or you are planning on overclocking and want to extract every last bit of performance from your processor. i did my last one, but the benefits arent that great. and it takes at least a couple of hours of drudgery to do it right.
for power supplies, enermax or pc power and cooling are the best, and antec also makes great power supplies. those brands are pretty much in a league by themselves, although there are a couple of manufactures who are coming on. get the best you can afford. please note that alot of manufacturers play fast and loose with those power ratings, as there arent really any standards. a 300 watt antec outperforms a 550 watt no-name supply, and probably even most of the name brands as well..