http://www.hotukdeals.com/?merchant_...rder_by=Newest
Usually some good prices on Dells found via that site.
Some have the business version of vista on though, I think what happens with some of those deals is Dell basically knock the equivalent of the VAT and shipping off the price of the business machine and let a home user have it for the same price it would cost a business.
I got my desktop though one of the offers listed on that site, Infact I did it over the phone and they seemed happy to sell it for the price i was getting the website to come up with (even though the evalue code if entered on the search would go to the bussness store)
My mate also ordered a desktop though one of those links and did it online and had no problems ordering.