Ive never built a PC. I was going to buy and Alienware for 1.4k (check post history to see pics) but I was told building would be cheaper.

How much cheaper are we talking? I want a top of the Line Computer and don't have much time on my hands so if I were to build one it would need to be easy for me where it wouldn't take days. I heard from others it would only take a couple hours but like I said I am a newbie. Also if it were top tier with I7 and 16gb of ram and all that how much would it end up being?