I went to Stone Island last year and will be going again in a few months.
We took a water taxi, but it was included in our tour price. We went horseback riding with Randi of Randi's Happy Horses. The price was $35, and it was alot of fun. After riding Randi took us to Victors. The shrimp were huge and delicious. I think the meal came to $12.
I have read you can do it on your own. I would not recommend paying for a ship excursion. Save your money and do it on your own.
1988 NCL Seaward
1990 RCCL Sovereign of the Seas
1994 Carnival Jubilee
1995 Carnival Sensation
1996 Carnivasl Holiday
1997 RCCL Legend of the Seas
1998 Carnival Facination
2000 Carnival Celebraton
2001 Carnivasl Triumph
2002 Carnival Spirit
2003 and 2004 Conquest (2004 bingo winner)