Try the "We Care Physicians Network (352.334.7926) and the Equal Access Clinic, located at the Salvation Army. Such programs provide limited services that are free or reduced in fees." Or you could call the Salvation Army in Jacksonville and see if they know of anything. I think the Salvation Army is affiliated with the Sulzbacher Dental Center for the Homeless in Jacksonville, (904) 355-6100. Not sure they can help you if you aren't homeless, but probably they could at least refer you to someone else.
www.dental.ufl.edu