Looking for advice on budget laptop gaming

I've been busy browsing around trying to find a good, cheap laptop for gaming. Hopefully some of you who know much more in this area can point me in the right direction.

Budget: around 600 but willing to push it to 700 for the right reasons.

Wouldn't like to go below a 15 inch screen, larger is better pending on cost

I am really in the dark as far as resolution goes. I would like the highest I can afford within the budget. If anyone could take a second to give me a quick run-down on resolution vs screen size in relation to gaming that would be wonderful.

This will be more of a desktop replacement.

Battery life is not important as when I do move around its with a cord.

I'd like to be able to play League of Legends, Heroes of Newerth, and SC 2 when it finally comes out. The higher settings the better for these but I'm not willing to go too far outside my budget.

Besides gaming it will just be an all around computer: watching a lot of movies, wandering the internets, music, word processing. Gaming will be the only major cpu/gpu sink.

160gig hard drive should be plenty for me.

I'd like to keep this laptop for at least 2 years, I live in the US.

I have also considered trying to build my own desktop or buy a pre-built desktop but am leaning heavily towards a laptop now. One of the reasons being that I would need the whole kit (monitor, keyboard, ect). The other being that I would need to buy an OS either way and if I buy a laptop I can get the voucher for Windows 7.

The problem I've had so far has just been finding a decent graphics card on a lower end laptop - so many are integrated.

Here's a few links with some possibilities I've been looking at:

http://www.newegg.com/Product/Prod [...] 6834115571

http://www.newegg.com/Product/Prod [...] 6834220570

http://www.pro-star.com/index.cfm? [...] odel=KHLB2

Basically I'm looking to get as much gaming power as I can out of a 600-700 dollar laptop. Any and all advice is greatly appreciated and if there is anything else I should be thinking about for this purchase be sure to chime in!