Don't know off-hand of an online source, but if you would PM me your email address then I'll send you some info on making the tanks.

For stuff like tank fittings, you could get these from sources such as www.bvmjets.com

Gordon

P.S. If you don't already have a source for the composite materials, you may want to consider Art's Hobbies (http://www.arts-hobby.com/) - that's who I bought my stuff from for the tanks I'll be making for my Hunter.