Keep some stuff in mind such as portability. So go for a 15.6" Model. Get an I3 or even better an I5 (either second or third generation) -- usually second generation is more common (Aka Sandy Bridge) ---- 3rd Generation (Ivy Bridge)
You will want around 300-500gb harddrive. You might have some music, photos, and videos here and there. A decent resolution also 1366x768 is usually the standard on the lower end laptops.
http/www.newegg.com/Product/Product.aspx?Item=N82E16834215403
This is the best for your money. IT IS THE LATEST IVY BRIDGE Processor (wanted to emphasize since I haven't seen many companies offer 3rd generation i5s on lower end laptops) even $1000+ laptops have second generation i5s so this acer is a GREAT DEAL!
http/www.newegg.com/Product/Product.aspx?Item=N82E16834310634
This lenovo is also a great buy and comes with windows 8
avoid refurbished, etc, you want something to last 3-5years and the two i mentioned will do that!
Good luck buying. The acer has 6 gigs of ram vs 4 on the Lenovo but trust me u wont ever use more than 2 gigs for "casual work" My computer has 3 gigs as we speak and it works beautifully.