In Georgia a WMA can be either private land leased to the state, or a part of the Nat'l Forest. For example I hunt a WMA in Oconee Nat'l Forest. It is Federally owned, but the state manages for Wildlife. There are other areas of Oconee Nat'l Forest that are not WMA's, so you would not need a special stamp to hunt them....only a regular hunting license.

Hope that helps a little.