Picking your first boat to build is not an easy choice. I decided to start from the very beginning with the easiest plywood boat I could possibly find and doing research before that even started.
Boatbuilding for Beginners and Beyond is a really thorough place to start. I thoroughly enjoyed learning the starting technique for building instant boats. Jim goes through the basics of boat construction techniques and explains how to build the Mayfly, a 14' sailboat. The book also includes the plans for several other boats.
Think I'm going to start with the Piragua, a double rowboat. Plans are included in the book. It takes two sheets of 1/4" exterior grade plywood plus some extra stuff that's already on order. I get to try epoxy and fiberglass tape for the first time, but I'm not going to glass the entire bottom of the boat. This one seems small and easy to pull together and is supposed to be a great first boat to build.
I would actually like to build the Mayfly as well someday, and learn how to sail. But this is seems like the right place to start.
They say a journey of a thousand miles begins with a single step. Welcome to step one!