Gaaaaaahhh!
Fiberglass.
Not only is it toxic stocky, unpleasant and generally evil stuff, but you need to already _have_ a boat shape to start with. I've done my share of repairs, and have built a composite (fiberglass) surf kayak. The main work though was strip planking a wooden plug for the mold. If I was building one boat, I could have paddled the mold (and had a nice pretty wooden boat) for less effort. Composites make sense if you are doing series production, or if you are very carefully (requiring careful design) making use of properties of the material (racing yachts etc) For _most_ one off builds it's a nightmare.
Otoh, epoxy _is_ a decent material for holding wood together. Not in keeping with the spirit of this board, of course, but for a kayak, a good recommenation for beginners (or anybody) is "stitch and glue" plywood. Beautiful/durable/quick-to-assemble designs are possible in this material. I'm fond of glued laptrake construction as well. The faerings and other small boats of Northern Europe have always attracted me.
Strip-planking is another option, but after doing the surf boat like that I'm not a big fan of the process.
Skin-on-frame: I've become a huge advocate for this construction, and probably won't build kayaks at least any other way unless there was a very specific reason for doing so. My boat is completely traditional construction, which means that the only tool you
need is a knife. Everything is held together with mortice-end-tenons begs and lashing. The only concession to modern times is the nylon skin (still sewn on as if it were leather) and hypalon paint (toxic, but very minimal exposure and you are never elbow deep in the stuff). Cotton/linen canvas and linseed oil based coatings are a less "modern" option.
Boats built this way go together very quickly and have a design elegance that I find very satisfying. See some picture here:
http://www.slinging.org/forum2/yabb/YaBB.cgi?board=1;action=display;num=11004114...I'm going to have to dissagree with english on this one and call reed rafts as being one of the easier primitive constructions. Some pretty sophisticated boats can be made this way given access to suitable materials. Telling about dugouts is that is one of the first types of construction to be abandonned once alternative tools/techniques are available. Not to say that some pinnacles of small craft design haven't been achieved - the war canoes of my area are possibly the prime example, although these are very large boasts. Staying within Canada, it isn't tough to see the technical superiority of birchbark canoes or the skin designs over smaller dugout craft.
Matthias