Heaps of ways to go about it. I designed and built a pair of F16 hulls out of foam and double bias glass in a female mdf jig.

But to go down this route you really need a fair bit of composite building experience or a helpful friend with said experience.

PM me if you need a hand with preparing the hull shape. I'm an engineer specialising in naval architecture and do that stuff all the time. Check out Gato's bloog on his F12 builds. http://www.gust.ax/

Oh, and don't go down the blue foam route. It might be cheap and quick to build but that'll probably be the only benefits with that method.