Yes, there are wild monkeys in Florida. It seems when they filmed Tarzan in the late 1930's, they released the 3 males and 3 females. Now we have 1000+ monkeys around the silver springs area.
Besides the very unique and amazing-to-see wildlife, the Silver Springs kayak run is absolutely stunning! It has crystal clear water with so many springs that have a blue glow to them.
We rented our kayaks through http://www.silverriverkayakrentals.com/ which offer single, double, sit in, on-top kayaks, so you can choose what you want. They also put in on the west end and pick you up 3-4 hours later on the east end. Cost was $35/each since we got single kayaks.
You can go through the state park and get an all day rental for $45/each, but you start on the east end. It took us a little over 3 hours to do it one way, so if you want to see the whole stretch, I suggest using the service we did. But if you don't want any time restrictions, then use the state park: http://www.silversprings.com/kayaks-canoes/