If you really want an in depth experience with Dolphins -- something more than a short swim with the dolphins -- this is the place to check out.
Discovery Cove Way
This is where my kids swam with the Dolphins. They have a really nice set up here and put on a good show, however, you have to pay an additional fee for the experience.
Sea World Drive
Swimming with Dolphins is an option at Sea World in Orlando. If you go to Discovery Cove, you get free admission to Sea World, however we never made it there.