that would give people here a better idea about the price range and features you want
Another possibility is to list the range of cpu features, RAM and hard drive sizes, and graphics card options that you would consider acceptable
It's my impression that affordable laptops often don't have very fast cpus. It's also not always easy to upgrade laptop memory: that depends on make/model. So be sure (before you buy a laptop with the cpu you think you want but less memory than you'd like) that you understand your upgrade options
You already told me why you want a laptop rather than a desktop. But if that reason is only short term, maybe you'd do better to buy a cheap laptop and save for a good desktop for your potential professional work. I have a $250 laptop and a $1000 laptop. I generally don't take the $1000 laptop anywhere -- because if I drop it, or if it's stolen, I'm out $1000 -- whereas if I drop or lose the other one, I'm only out $250. You're likely to have much faster processor options, much larger RAM and hard drive options, and much better graphics card options in a desktop
I don't do video-editing work, so I really can't advise you well. You might want to read reviews: I often read newegg and compusa customer reviews when deciding what product to purchase. Another thing you might want to do is to play around with configuring machines on mfr websites and save screenshots. Don't get in a hurry. Pick 5 or 6 companies and just play around with configuring to see what your options are; check out the company reputations online; google for what video editing folk say about certain companies and configurations
Here's a company I don't really know anything about, but it gets good reviews at resellerratings and the lowend price seems reasonable to me, though at the high end I don't think I'd drop $5K on a laptop
Is That A Notebook? MALIBAL's Six-Core, Dual-GPU, Speed Demon
2:00 AM - November 3, 2010 by Thomas Soderstrom
http://www.resellerratings.com/store/MALIBALI configured a 15" Lotus notebook with 2.8-3.46GHz i7 (4MB L3 Cache), 8GB 1333GHz RAM, GTX 460M graphics, 750GB 7200rpm hard drive, for about $1550; that doesn't include the operating system; they'll knock $50 off it you do a bank transfer instead of using your credit card
http://www.malibal.com/lotus/