I too just bought a laptop from Dell. I went to http://www.edealinfo.com/Misc/dell.shtml
They basically tell you how to get the best deal from dell. It takes you to Dell's own site and you just customize the laptop to your specifications and then use whatever coupons are available at the time. I bought mine on Friday and used a coupon for $100 off. Today that same exact computer came with a coupon for 10% off...so basically I paid $41 more on Friday than I would have today had I bought it.
It really depends on when you catch the deal, but edealinfo puts together the best deals...let's you know which coupons are valid for the particular deal!!!