You'll need 12-13 sheets of drywall, plus nails/screws, tape, mud (joint compound), finishing tools, etc. Will you also need to drywall the ceiling or is there a ceiling already in place? I have no clue what materials cost there, but it is a LOT of work. Seriously. Unless you are a very advanced/experienced do-it-yourself type, I would not attempt drywall.
However, if you meant that you want to hire someone, it could be that with the economy the way it is, it will be easier than usual to find someone willing to do a small job. A few years ago, no contractor around here would want to bother with a small job, but now I think people are happy for any work they can get.