Who owns the land? My father sold me a piece of land in 2002 and told me not to fill it untill he died.

I am assuming that the deed given to you was validly executed.  Under Georgia law, the deed was a good conveyance to you but the recorded deed given to your sister would take priority assuming that she was not aware of the conveyance to you.  If she was not aware of the deed to you then she probably has good title.  If she knew about the deed to you then you have some good arguments that your deed controls and you own the property.

I believe your sister will have the better claim to title.  If your father gave you a deed and asked that you not file it until his death, you did the honorable thing to wait.  However, if in the meantime he gave another deed to your sister and she went ahead a filed, she will almost certainly have a superior claim.  Your question gives no hint whether your father may have forgotten that he gave you a deed earlier, or whether your sister knew of your deed.  The answer to these questions will have no bearing on the outcome, but may help you to better understand the reasons for what happened.  A brief conference with a good real estate lawyer in your area will confirm the title status.