We did Athens on our own before the start of the cruise. Athens Walking Tours is great! And our transfers from Airport to Hotel and Hotel to Ship were arranged by John at Athens-Taxi.Net He also arranged a guide/driver for a day trip to Delphi. All were top notch and reasonably priced for the six of us traveling together.
WE did Capri and Sorrento on our own - don't miss the kitschy but wonderful Blue Grotto or stunning AnaCapri