Hi Brian, I used to read boat building articles in Popular Science magazine many years ago when I had a subscription so I do not know if they still publish those.... but when they did, they had plans available including for the sails that were made out of plastic tarpaulins for a very low cost; so check that source out. Another source for do-it-yourself sailmaking is Sail Rite at: http://www.sailrite.com/ and their sail kits at: http://www.sailrite.com/sailkitpricing.htm

Good luck!

Mike