First off, thank you! Secondly, a lens choice is very very much a personal choice, not to mention an expensive one. The lens I used in almost every one of my shots is my general "walk-around" lens (which is in need of being replaced as it has some nicks on the glass). I had two other lenses with me, a telephoto that I only used for two shots, and a low light lens, which I only used on a couple of rides. Everything else I shot was with my main lens. As far as picking which lens you want, a good place to start is a place like borrowlenses.com. You can rent a lens for a day or two, or how ever long you want, and then try it out to see if you want to plunk down the money on it. My two previous trips, I rented a wide-angle (that stopped just short of fish-eye). I enjoyed it, but am not ready to plunk down the cash for it. My personal process is to look at lenses on
Amazon just to read the customer reviews. Then check out the lens on a site that lets you borrow them. As far as a tripod, I can't state enough how much a tripod is needed to get good night time shots. Yes, it's a pain to carry around the park, but looking at the photos it helps you get should make it worth it.