I was wrong about one thing. I thought that in addition to the two White Union Calvary regiments that there were two regiments of Florida former slaves. But I was wrong, while they fought mainly in Florida raiding and burning plantations on both coasts, one of the U.S. Colored Troop regiments in Florida was made up of slaves from DC, Maryland and Virginia (the 2nd US Colored Infantry) while the other was made up of slaves from Louisiana (the 99th US Colored Infantry). It doesn't look like there was any organised free black units from Florida.
But there were two smaller (really only half sized if that) official Union regiments from Florida, the First and Second Florida Calvary Regiments. What is interesting is that while most of Florida's organised troops fought in the Army of Northern Virginia or in the Army of Tennessee, back at home because there were a number of unionists formerly from the North as well as cities like Jacksonville, Key West and Pensacola where big portions remained in northern hands throughout the war, that Florida was basically the "Wild West". There were tons of little skirmishes between militias on both sides mainly fighting over cattle. One irregular Confederate unit even called itself the "cow Calvary" as they rode defense on the herds.
JJ Dickison was one of the more famous/successful irregular confederate leaders in Florida and is still the only person to have led a Calvary unit to seize a US Naval ship.
Here's an interesting little summation.
http://mobile.nytimes.com/blogs/opinionator/2013/12/19/floridas-cattle-wars/?referrer=