Kevin--no one answered you. Air tricks are tricks w/o use of the wake. An air roll is a back roll in the flats. I'd love to give you a perfect description of how it's done, but I've only hit it 3 times (out of 20 or so tries).
That won't stop me from giving my two cents
drift away from the wake on your heels (on the left side of the boat if you're regular), set a *hard* and quick edge (I'm most successful if I focus on putting a lot of pressure on my front foot), and let the board release. If you stand tall and bring the handle to your lead hip at the same time, then the board will rotate up and around just as with a back roll. Seems like this trick really wants to go to revert (but I've been too chicken to let it).