Hi mommom, welcome to Cruise-Chat. There are probably 100 or more posts on doing this. It's probably the most favorite thing to do. Here's
a link to the ferry schedule. The cab fare from Havensight to Red Hook is $18/pp, the cab fare from the dock to Trunk Bay is around $4.50/pp, the ferry is $6/pp from Red Hook, the entrance to Trunk Bay is a couple of dollars per person. If you use your "find" feature in the upper left hand corner, type in Trunk Bay, it will pull up all the posts made. I think there are some pictures, too. You're going to LOVE it! Hope this helps. Best wishes and have a fantastic cruise!