Tonka (Tom's sister) took us on this tour and shared wonderful insights both into the locations/settings used in GOT as well as the happenings on set, as she herself was present on the sets, as an artist.
Tonka also had a photo album book that helped us relate the locations with the specific GOT scenes/episodes. She was patient and explained well. She also did her best to answer the numerous questions we had.
Great experience - a must do in Dubrovnik especially if you are a GOT fan.