I just bought a new Dell laptop and I love it. It's a Studio 1558, i5, 6gig ram, 500gig hd, 1080p, surround sound, 1 gig radeon and I got it for just over $800 + tax with free shipping.
I would recommend watching Dell Outlet for refurb/extra's and keep an eye on the Dell Outlet Twitter page for coupon codes. Actually, on slickdeals.net there was just a code for 20-25% off any Dell Outlet laptop purchase. These come with full warranty's, some are even new builds that people cancelled after the build was done. Great discounts.
You don't want to build a laptop, it's not cost effective like a desktop can be. Also, you will probably be better off not getting Office packaged on the device but get it from somewhere else cheaper. Especially if you can get hold of a .edu email address (education discounts 4TW!).
Just my .02
Black Friday is great if you can wait but the best laptops never go on frigging sale LOL!!! doesn't stop me from spending too damn much money though

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