I'd normally recommend an LG notebook. I'm probably the only person in the world who loves their notebooks (which are generally marketed as business notebooks). Excellent manufacturing quality and probably the best non-glare displays on the market, but I think LG is above your budget.
Anyway, this one seems to be a gaming notebook with the best value for money atm:
http://www.notebookcheck.net/Review-Medion-Akoya-X7811-Gaming-Notebook.28166.0.html
A German review site called it the current "high-end gaming bargain". This page of the review is in German, but you can scroll down to see some benchmark comparisons for demanding games: http://www.notebookjournal.de/tests/laptop-review-medion-akoya-x7811-hd5870-nkmo-1131/2
The Akoya X7811 seems to be above your budget as well (€ 999 = £ 875), but I thought it was worth mentioning.
I generally recommend sites such as notebookcheck.net instead of internet forums, where the first one says don't buy a notebook, the 2nd one Asus, the 3rd Acer, the 4th one Dell and the 5th one don't you never EVER buy a notebook for gaming. 
Try this instead: http://www.notebookcheck.net/Purchase-Consultation.13212.0.html
