Crook & Crook

You don't need a saltwater fishing license if you fish from a charter boat in Miami—but you do if you're renting your own boat. (Neither do you need a saltwater license if fishing from land or a structure tied to land.) Freshwater and saltwater licenses for non-residents cost $17 for three days, $30 for seven days and $47 for a year. These can be ordered online here, but tackle shops such as the excellent Crook & Crook also sell them. While you're at it, this is the place to stock up on all manner of sports gear, from fishing lines to radars and rain jackets.