zaptor: New Dell Inspiron N15R for $1399? (i7-2630QM, 4GB RAM, 500GB HDD). Extra $225 for 3 year warranty. Only available with Win 7 Home Premium though.
I'd be wary of purchasing a laptop from a consumer range, for business use. I made that mistake with my last Dell. I'd been a happy Latitude user for years, but these were all work supplied laptops. When I became an independent contractor, I had to purchase my own laptop. Trying to get the best bang for my buck, I purchased a Dell Studio (1535), which saved me about $1000 on a similarly specced Latitude.
Out of the box, the build quality was poor, and the keyboard quickly developed an annoying squeak. But that paled in comparison to the daily (and this is no exaggeration) BSODs I experienced. Long story short (as the long one involves over 6 months of frustration with Dell support), the laptop didn't take kindly to having a secondary monitor attached... until I disabled Aero in Vista.
In addition to that ongoing problem, I had the keyboard & trackpad replaced 3 times in a two year period due to a trackpad that kept failing, and the HDD replaced within the first 6 months (which got me a free upgrade from 250GB to 320GB :-)). There were also design issues with the laptop which indicated that it wasn't really intended to be used as I was using it. The most glaring was that the VGA cable for my external monitor couldn't be screwed into place, so I'd lose monitor connectivity a few times a day.
Seconded, avoid anything in general from retail chains like HN, DSE etc, as they are almost entirely consumer platform and designed with price and specification in mind, and this generally requires a drop in build quality and warranty to match.
i've had acer, toshiba, HP and now Lenovo - all 'business' models. Mostly been OK. So far i'd have to say I've had best experience with the Lenovo (T510) as it has been really solid and seems to have good software/support etc.
Whatever you get, make sure you get a 3yr warranty. If you're actually using it as a mobile laptop then something will probably go wrong. Many 'business' models already come with 3yr (good indication that its a business model) but if not its usually $100-$200 for the manufacturers warranty extension and well worth it (NOT DSE/HN ext warr!). Remember if its for the business then the CGA does not apply.