If you have shop put this together for you, you probably will have to buy the components from them rather than shop around for the best deals on individual parts (or buy from NewEgg which many system builders do).
Also, if you buy from a good shop with competitive component prices (should have everything listed in an up to date shop catalog), the guy who helps you out will probably be willing to teach you whatever you need to know. It's more or less how I learned how to build systems myself.
Most shouldn't charge more than $50-100 to put it together and make it post successfully. Some will do it for free if you buy everything from them. The OC on your CPU will probably be up to you though so start reading up on that if you want the most out of your CPU. If the shop's really cool, the tech may actually help you overclock your system as well.







