Florida beaches are useable more on the West Coast than the East Coast during the Winter. In other words, the Gulf of Mexico is warmer than the Atlantic Ocean. This past Winter was warmer than normal during the December and January time frames and the beaches were crowded with plenty of swimmers on the West Coast.
Obviously the temperatures are a little warmer the farther South you go so along the West Coast you have Clearwater, St. Petersburg, Sarasota, Ft Myers, Naples, and other smaller coastal towns.
Here is a link to get free travel guides from the State.
Florida Travel GuideAs a point of reference, you can get travel guides from every State if you do an internet search for the OFFICIAL tourism website for the States that you may want to explore. We started a file of all of the different ones from different States that we have visited and they usually include a nice travel guide as well as various maps. All are free. :)