Travel with Pets - State Document Requirements for pet travel

I have 2 small 6 lb dogs so am traveling Thursday with both in one carrier on American Airlines out of JFK (NY) to TPA (Tampa, FL). American Airlines says they do not require a health certificate but some states have specific requirements so I should contact my Vet or State Authority. Here is the situation - one of my dogs is a senior - and there is no way I will vaccinate her at her age. My vets never give me a problem about this since it's widely accepted we overvaccinate our dogs...especially little guys. I tend to vaccinate once a one year Rabies every 3-4 years and have gotten titers in between a few times. It's crazy that a one year rabies was still fine 4 years later. Titers are ridiculously expensive - the last time I had exams and titers for my two it cost me $1000. I really can't afford this right now and the last time they were seen was about 8 months ago.

Here is my question -- how do I find out what Florida requirements are? Has anyone here flown out of NY or out of Florida with their pet and did you have to provide any documentation? Any suggestions for flying two dogs in one carrier also appreciated! Im not that worried - they have been on trains and ferries in the carrier together and I just read AA allows carriers about 6" wider and 6" longer than what they are used to so they should be very comfortable. Their easygoing good dogs - so all should be fine. Im more concerned about documentation I may need though. Thanks In Advance!