All the laptops I've bought for myself or relatives over the past 10 years or so have been ThinkPads from the IBM Certified Pre-owned Laptop site
I like ThinkPads because they are built like tanks (meaning strong, not heavy), have the best keyboards of any laptops, and being targeted at IT departments rather than the folk who shop at Best Buy or Staples, their on-line support is top-notch if one is technically savvy. There is also an extensive on-line ThinkPad user community.
Right now, the site is having a 20% off sale and including a 1-year extended warranty for free. Looking there, I see they list a T400s with a 2.4 Ghz Core 2 Duo processor, Windows 7 Pro, 4GB RAM, 120GB HD, DVD-RW, a/g/n WiFi, Bluetooth and a built-in camera for $369. With 20% off, that comes to $295.20. The model number is listed as T28153YU, which translates to 2815-3YU, so you can go to the Lenovo Support page
, enter 2815-3YU in the Quick Path box and find more information (such as that the screen resolution is 1440x900), download user guides and maintenance manuals, etc.
That particular item may be gone by the time you look, but their stock changes daily, so if you keep looking and do your due diligence, you can come up with some great deals. They also have free shipping and a 7-day money-back guarantee.