I just moved to this area and intend to hunt for artifacts in the Cape Haze area. I have a boat so some of the islands are doable. Would be willing to take fellow seekers along. There must be known sites in the area to hunt.
Yes, the area has a lot of history. To your south is a State Park, where it is forbidden to detect. All of the islands are private property, so be cautious of where you go without permission. The beaches are all free (expect the state parks, where it depends on the head ranger)
Research the Florida section of Treasure Net for more on the laws of the area.