Public Transportation from the Airport: Aside from taking a taxi or the Keys Shuttle (305-289-9997 or visit:  www.keysshuttle.com) - you have the following options:

KeysCity Bus
stops at the east end of the terminal, on the roadway curb (tel. 305-809-3910. 
Miami-Dade-Monroe Express Route (tel. 305-891-3131.
Greyhound has an on-airport bus station (305-296-9072 or visit www.greyhound.com) with available small lockers.

The new 'Key West Transit' site - http://www.kwtransit.com/ - will offer a Live Bus Map and Arrival Times.

Google Plus One