Demo as many as possible, Jackson 2 Fun, Wavesport Siren (if you're looking for something older/cheaper), Dagger Mamba 7.5 (just a river runner, no play), Dagger GT, G-ride... keep trying boats till you find one you like.
Skirts, IR makes some good ones, as does WildWasser. The Harmony skirts aren't great, though. I like the SnapDragon skirts as well. The kind of skirt you get is not really as important as the boat and paddle.
As far as paddles go, I would say get a good one from the start. I started with a cheapo one, thinking it would get lost or broken pretty quickly, then got a good one and couldn't believe how much difference it made. I have a Blue Pool paddle, which I love, but they can be kinda hard to find. AT makes some good paddles as well.