The cheapest
MacBook is $1099 unless you buy from BestBuy, MacMall or the like, in which case you can save about $50 or so. Or, if you're a student, Apple offers a discount, but I'm not sure by how much the price is reduced (I haven't been a student for many years LOL). Probably in the range of $100, I'd guess. I think they also toss in an iPod.
If you're interested, Apple also offers refurbs, but you'll have to check the site for prices - they vary with specs. They're fully warranted, and the couple that I've actually seen were absolutely perfect and couldn't be picked from among new machines.