We visit Block Island several times a year on our 35'' sailboat. (We sail from Newport, RI) You have 3 options for accommodations: 1. Dockspace - Block Island Boat Basin is the only marina that does not raft. If you intend to stay there, contact them NOW and return to them the dockage request form and a deposit. They do not take bookings over the phone. Dockage is expensive. Both Champlins and Payne''s raft DEEP if necessary. Champlins is approx. the same cost as the Boat Basin but they do have a pool and some other amenitites. They take reservations and have a min. number of nights. Payne''s is cheaper than the other two and does not take reservations. I have never managed to get a mooring; they are inexpensive and tough to come by. Anchoring is NOT that great. In a blow, I have seen numerous boats bust loose.
Block Island is great for its natural beauty coupled with a relatively low number of people. I would strongly suggest that you either bring a bike or rent one on the island (you can rent them right at the Boat Basin or Champlins). Depending on what you are into, the island has numerous excellent beaches, several lighhouses, and some nature reserves. You can also go horseback riding, rent a canoe or a kayak, go scuba diving, and they tell me the fishing is good. Plan on being outnumered by powerboats 50 to 1. Strangely enough, many/most of these folks never seem to leave their boats! Shopping is fair at best. Restaurants vary from poor to excellent and are generally expensive for what you get. There are a few decent bars and you can usually catch a good live band most nights. One warning: I would strongly suggest making the approach to the New Harbor channel during the daylight and good visablility. Study your charts as the breakwater on the southside of the entrance is actually south of the actual channel. Good luck and have fun.