Here's the address for Florida returns 1040, 1040A, 1040EZ
Department of the Treasury
Internal Revenue Service
Austin, TX 73301-0002
If you are enclosing a payment please send to this address:
Internal Revenue Service
P.O. Box 1214
Charlotte, NC 28201-1214
1040X with or without a payment:Department of the Treasury
Internal Revenue Service
Austin, TX 73301-0002