To anyone like Melissa who asked below, where to find Captain Spiros to book for a trip:
If you find the Tsilivi Watersports (the official one with a huge sign up, where Parasailing and things go from) and head to the left of this, away from the main beach, you will be able to follow the harbour road which curves around to the right. From the watersports hut you will be able to see across to where the road ends up.
As you get around to where the boats are in the harbour area, there should be a little stand with Levante Boat Trips on it.
Most days after trips, Captain Spiros will be found somewhere along the beach handing out leaflets and having a chat :)
Hope you find him:)
If you can't, just ask around, someone will be able to direct you, he is well known in Tsilivi.
Enjoy:)