Saul:
The short answer is yes, there is still an elevated risk of hurricane activity in Florida at that time of year, however, the Sarasota/Tampa/Clearwater area has not experienced a hurricane in quite some time. Often in late September through October, Tropical Storms would be a greater risk in the Gulf of Mexico and they often recurve toward the northeast and make landfall on Florida's west coast. Hope this helps you in your planning, however, I wouldn't necessarily cancel a trip because of that threat. The chances of any one small piece of shoreline getting a direct hit from a hurricane are mighty slim. I think that one of our Moderators, HanKFranK, has commented on this in the past.
Cheers,
ED

Added: I should also mention that one of our site meteorologists, Rich B, is from your neck of the woods (U.K.) and may be able to help you with the statistics that you are seeking.