I buy my parts at Canada Computers and the parts have been fine since. I know some people in IT and they advised me to stay away from Tiger Direct, so take that as you will. Of course you can create systems on sites like Dell. They will ship the computer to you. But you will probably end up overpaying for these systems and you will probably get (with Dell for sure) proprietary motherboards and power supplies. If you go to a retail store, like CC, the people working there will be able to help you out with picking out which parts you need. And most of these retail locations will build the computer for you if you are not able to do it yourself.