"I've been reading all about European sewn-plank boats, but I think I'll make a leather boat first since it's cheaper (for one reason) and the materials are quick and easy to get."
Jeff, sewn-plank should be easier as the planks form the boat shape for you. Would be nice to split out and hew the planks but purchased sawn will have to do for me.
As soon as I get over my immediate health challenges I will be doing a basic sewn plank boat. Money and lack of assistance have put my plans for a full-size sewn-plank version of the Roos Carr boat on hold but a utility craft is possible. I would take the Chilean Dalca as my model for the technigue to use with reference to the Ferriby Bronze Age boat that was reconstructed as a half-size version.
http://www.rivenoak.co.uk/1643/1685.html
Point is that one can create a basic boat using planked pirogue methods where the side planks control the shape.
http://books.google.co.uk/books?id=cmQb ... ue&f=false
Then the bottom plank can sewn on with its ends cut down and then curled up to act as stem and stern.
If only short planks are available then they can be sewn together. Spruce roots are used as thread in the Baltic area but I have experimented with bramble stems that would seem to work as individual stitches. Caulk and plug with beeswax/tree resin/lanolin.
Full-size Ferriby being built in Falmouth, England this year starting April and a Dover Bronze Age Boat is well under way.