Cameronian,
I'd second Mike-Bracknell's suggestion of the Apple refurb store. If you've got a local friendly Apple reseller there may be some ex-demo options or some excess stock they're trying to clear.
I would be a bit weary of eBay, you might end up with something like my "spare" MacBook Pro that's sitting next to me at the moment.... works perfectly, but suffering a little bit in the cosmetic section after it fell it onto a concrete floor one day.
