In the past, I built all of my PCs. Now I need to upgrade my old PC before it dies and I'm planning on going with Windows 7, but I don't have time to build it myself.
I don't want to go with a Dell or HP type shop. I want to buy from a place where I have a selection of parts and can have some choices. Here are a few I've found (though I haven't tried any of them yet):
If you have the time to choose all the parts NCIX.com USED(as in I am no longer sure if they do or not) to offer an assembly option at checkout for an additional 50$. They won't install your OS or anything like that, but what they will do is put all the components together and make sure it posts which will save you a whole world of trouble. Be sure you order proper thermal compound though or they'll stick you with the crap that comes with whatever HS/Fan you buy for your CPU.