The shuttle bus from the ship does not take you to the railway station and taxis drivers are a bit reluctant to move of the rank to do such a run but you could take an normal bus from the ship to Livirna cost 1 euro single. The bus from the crusie ship dorps you off in the centre by an information kiosk. There is an archway leading past some shops, through there and cross the square. Take a number 1 bus to the station, cost another 1 euro. The the train to Pisa journey time around 15 mins and costs 3 euros single. There is a tourist info point to get you a free map of Pisa. When you arrive back from Pisa there are taxis at the station but not many and they disaapear fast so be quick off the train and allow plenty of time to get back to the ship. If you used the bus option going to the station you know the pick up points. Someone else might come up with a taxi price from the ship to the railway station but don't know that, but using the bus it is a very cheap option.