I need quality computer parts, but I don't want to pay an arm and a leg. I know of NewEgg and TigerDirect, but I have experience with both, and I'd rather do business elsewhere.
Amazon also. There are parts where it's reasonably safe to order used parts such as SSD's, graphics cards, sound cards, monitors, and you can save money that way from Amazon as well. I'd probably go new with a warrranty for a motherboard, and CPU.