congrats on the boat, yep I recently made the plunge myself with mine, and i have been putting it to good use every chance I get.... Please post pics of her so we can see it!!
Eventually I am going to be getting a 'seagoing' boat myself. The one I have is super sweeeet but it's a flats boat really, and yes while I can take it out on the ocean and go a few miles out on a calm day, those days are rare and it's best inland or right on the coast or ICW or rivers.
I used to be stationed in Key West and can attest there are plenty of fishing areas AND metal detecting / diving areas around there.... sugarloaf key is one in particular, I had one area i was pulling all kinds of stuff out of, found a small cache of silver dollars, among other things, but alas, got transferred...baah!!
Watch out for the state parks and other certain areas but it's prime pickins down there. I wish you the best of luck and hope that very soon you can post pictures of the treasures you are finding.
Aaron