You can build a very nice stitch and glue "tortured plywood" canoe called the "SWEETDREAM", weighing about 30 lbs and can be built weighing quite a bit less. Tortured plywood refers to the plywood being bent in two directions at the same time, not the Bush adminstration trying to extract information from it. Mark Pettigill (?sp) wrote a book "Building Sweetdream" which explains how to build it and gives plans for three lengths, about 12', 13', and 14'. I built three, two at home and one at an Assembly in the late 90's. Mark paddles it with a single blade, kneeling, with butt on a pedestal (plans in book). I like paddling it sitting sitting on a pad on the bottom with a double blade. It tracks good but I wanted it to track stronger, so I added a small skeg to two of them and firmed them up to my wishes. Changed the rocker on the third to improve tracking, but the man who bought it has never put it in the water so I don't know if the change worked. Cost is about $300 for two sheets of 4mm marine plywood(cannot use cheap plywood), epoxy, fillers, glass tape, paint ect.
If you are very large the "SIX Hour Canoe" could work. There is a book "Building The Six Hour Canoe" that explains construction. Easier, faster and cheaper to build, I don't like it in the wind, think it's too big and it weights 35-45 lbs. It can be built with cheap plywood- just check for and avoid voids in the plywood.
If you weigh about 150lbs or less, Mystic Seaport sells plans for a similar but smaller canoe called the Mystic River Jellyfish. I fostered the construction of 15 canoes of a similar design in a parent/child boatbuilding course. I like this canoe much better than the six hour canoe and it can be built for $100 (using cheap plywood) or less if you have a lot of epoxy around.
If any of this interests you, I could give more info in a phone call