The dolphin experience is in Anguilla. The name of the company is Dolphin Fantaseas but their website was not working when I last checked. To get to Anguilla you need to go to the french side of Sint martin and take the ferry to Anguilla-be sure to bring a passport or birth certificate and picture ID as you are entering a different country. You can take a cab from the ferry dock to dolphin fantaseas. I believe it was quite a bit cheaper to do it on your own but you do need to budget for the cab and the ferry too.