Just got back from Key West yesterday on the bike, however we didn't camp so can't help you out there. Tons of stuff to do - Duval Street at night is a blast, the sun sets are incredible, Hemmingway's house tour was pretty good (ususally don't enjoy those things), lots of great sea food to be consumed (along with your favorite drink), plenty of sunshine to enjoy. Check out any of the keywest searches and you can find things to do and hopefully find some campsites. Enjoy!!
Check out the campgrounds in the three state parks in the Keys, John Pennekamp, Long Key, and Bahia Honda. We rode a glass bottom boat out to the coral reefs from John Pennekamp a few years ago and really enjoyed it.
wbass, glass bottom boats are the coolest thing. Straydog, IMHO you should ride through Silver Springs on the way down. Some of the most pristine fresh water in Florida. Do take a glass bottomed boat ride. Several TV series were filmed there if you are old enough to remember.....Tarzan, I Spy and Sea Hunt.
I haven't been on Hwy 17 for many years but I bet that would be a trip on a bike. I remember when I-95 was not there and my Dad still got us to Florida very quickly in the '62 Pontiac Bonneville with the 421 cubic inch, 3 dueces, and the top laid back! So much to see in the south, have a great trip.