Go to the
New York EZ Pass website and sign up for a toll tag. The tags are free and there are no fees except when you pay a toll. Keep a credit card on file and it replenishes automatically. Here is a list of
states that honor NY EZ Pass.
Note that Florida uses SunPass and you'll need to go to the
the Sunpass Website and sign up separately for that program. There are a bunch of tolls on that BeeLine Expy in Orlando where the SunPass would be handy.
That said, I would have to agree with the other posters that from Lake George, you pick up I-88 out of Albany to Binghamton then I-81 south. While it's tempting to take the thruway to the TZ bridge, if you don't west on 80 in NJ to pick up 81, you are doomed to fight traffic through Philly, DC, and Richmond all the way to Florida. Going through the mountains on 81 is not only prettier but less stressful IMO.