Well if you don't want to build it yourself, then you should go to your local computer shop and have a tech build it. Don't go to best buy, Geek Squad is horrible, they know nothing from what I've been able to tell. Also avoid Circuit City's Fire Dog , they're idiots as well.( I called in about a x1650 for my HTPC since it supports HDCP and the guy called it a ubber high end card).
If you have a store like PC Club, they're great, and they have good rates. Or get someone you know to build it, or maybe arange something with someone on the board that lives near you?
Back on being mobile - ASUS G551- 15.3" 1080p - Core i7 4710HQ - GTX 860M - 16GB DDR3 1600 - 512GB Samsung 850 Pro - Steam ID: TheOtis