Popular trip with cruise ship visitors, so they pick up at the cruise ship dock in Havensight (St. Thomas). Not sure if its also available to the ships that dock in Crown Bay; if so they would likely pick up there also. If you are visiting on a cruise ship check the excursion list to see if its on there. If you are staying on island then you'd need to make a reservation. If its just a few people in your group they would try to fit you in with other bookings; they have a minimum passenger requirement for going out. Its around $45 an adult. Its a high speed thrill boat ride, about 30 minutes long.

--Islander

A quick Google indicates that it's on the majority of tours offered by the cruise ships including Disney which docks at Crown Bay. There are some trip stories on various sites which verify that they do operate out of Crown Bay also.