Well I can't really speak for any dispatch frequencies or anything that would be strickly related to the specific company but you should be able to hear them talking to Atlanta Approach/Departure and such.
Clearance: 118.1
Approach North: 126.9
Approach South: 127.9
IFR Arrival North: 127.25
IFR Arrival South: 118.35
Departure North: 125.7
Departure South: 125.0
Listen for something with a Lifeguard callsign. Chances are good they will not be IFR but prior to them taking off of the Hospital or any place within the Class B they will have to call up Clearance and talk to one of the approaches.