The route of the number 150 "Airport Flyer" Miami-Dade County public bus has just been expanded. If you are staying in ANY hotel, guest house or hostel between 44th St. (Fontainebleau/ Eden Roc area) and the southern most tip of Miami Beach, you can get a fast cheap ride from (and to) MIA for $2.35 (exact change required - coins and dollasr bills accepted) on a modern bus, fully equipped with spacious luggage racks.
The bus leaves MIA, makes one stop at the Earlington Heights MetroRail station and then runs nonstop to Alton Road/41st Street 9nice for us folks who atually live in NB!) and then south along Indian Creek Drive (one block from A1A/Collins Ave.) to 26th St then south on Indian Creek (1 block from Collins/A1A) to Lincoln Rd. and 17th St., then south on Washington Ave. (2 blocks from A1A/Collins) all the way to Miami Beach's southern tip, Then it rurens arounn and goes north on those same streets all the way to 44th st. and Collins, then turns, goes back onto 41st st. and back to MIA. It runs about every 20 to 30 minutes between about 6 AM and midnight, takes about 20 minutes to get to and from Miami Beach, and stops every 2 to 4 blocks once on the beach.
If you're heading to downtown Miami or anywhere else on the MetroRail route, it's an easy transfer at the Earlington Heights station, 10 minutes from MIA and the only non-Miami Beach stop.
Between 21 St. and the city's southern tip, you can ride the local shuttle buses for a quarter. I strongly suggest NOT renting a car at MIA to get here - use public transit (or a taxi if there are a lot of you or if you are heavily laden) and rent a car IN Miami Beach for traveling to and from other areas. Just about everything bad you've ever heard about South Beach parking and the towing companies is true and then some. If you MUST bring a car here, garage it and use itonly when you have to.
Further info available at 305-770-3131 or 305-468-5900, or www.miamidade.gov/transit.