Se use Sibley's for birds all over the country. But we also have this one:
[ame="http://www.amazon.com/Smithsonian-Handbooks-Birds-Florida/dp/0789483874"]Amazon.com: Smithsonian Handbooks: Birds of Florida (Smithsonian Handbooks) (0635517083873): Fred J. Alsop: Books[/ame]
Yeah, it's hard to beat the Sibley guide for all U.S./Canada birds. Fabs listed a fine reference geared for Florida. I'll also mention the Kaufman guide to birds that I really like as a smaller, field guide. Kenn Kaufman used photographs (carefully adjusted to show scale and key ID marks) and it is small enough to slip in my bag during a trip...unlike the Sibley guide that stays on the bookshelf back home.