Thanks all for the advice! Those pictures with the fiber glass are great too!
I ended up calling a manufacturer of wooden fixed pitch propeller blades for the aviation industry and asked one of the engineers what they used to coat their blades.
They said that they used "Spar Urethane", but that the finish had a shorter wear life than "Marine Spar Varnish." Apparently when a crack would develop in the hard urethane coat it would peel up and take off a good chunk of the finish, while the marine spar varnish adheres better, and isn't as brittle as the super hard drying urethane.
Since this is my first set of blades, I have decided to forgo the fiberglass route.
I've decided to stain and seal with a light Minwax wood finish, which claims to stain, penetrate, and seal. Then I intend to put on a few coats of Minwax Helmsman Spar Urethane. The Spar urethane claims that it can expand and contrast better than regular urethane. I got all of this from my local Lowe's hardware store. I want the blades to look good since they are my first.