I second the recommendation to shop the Dell Outlet web site or call one of the Outlet sales rep's directly, as the site can be a little hard to navigate.
I have purchased Dell refurbished equipment for 4 years at work, laptops included. I like to stay with the Optiplex and Precision line of desktops and the Latitude line of notebooks......the refurbished models in these lines INCLUDE a 3 year warranty from Dell. Others include a 1 year warranty.
On the rare occurances where we have had a problem with a refurb unit, Dell has fixed them within days.