I'm just about finished decking over a drift boat I rehabbed a few years ago. In addition to reading a couple of the books mentioned above, I spent hours and hours (possibly as many as I spent working on the boat) googling to figure out proper construction techniques and the design features I wanted.
Since I decked over an existing hull I didn't have to figure out which boat to build, but figuring out how to properly do all the work to deck it over intimidated me to a degree. Beyond figuring out the layout and dimensions for bulkheads and hatches, I didn't want to experience some of the epoxy or paint failures I'd read about that would require extra work to remedy.
I found a lot of good info about wooden boat building on: Wooden Boat People - By McKenzieDriftBoat.com
Late in the game I discovered the "Whitewater Dories" Facebook group, which is very supportive in answering questions you may have along the way. Also, a great place to ogle finished boats.
I read how-to articles and watched the videos put out by westsystem.com and jamestowndistributors.com
Another big help was going to see some finished dories (or that were partially finished) that were near where I live.
Figuring out where to buy supplies (hinges, latches, rubber chine strips, epoxy/fiberglass, wood for framing, etc) turned into another large research project.
I have a spreadsheet with many of the weblinks I referenced. PM me if you'd like me to email it to you.