You need to pop into a travel agent or have a look on the web or teletext as Thomsons; Island cruises and Ocean Village all do cruises leaving from Palma flying out from the UK. I am cetain there will be a few more but I am not a travel agent, you could contact this site 0800 091 1629 they have a specialisied cruise department.
We've done the Med twice with Thomson departing from Palma. We had a fabulous time both times. Once we did a cruise and stay...one week cruise followed by a week in a Thomson Hotel on Mallorca at half board. Actually the cruise was so good we asked to stay on a second week and forego the week at the hotel, but the cruise was fully booked that week. It didn't matter as the week at the hotel was excellent as well. We highly recommend Thomson for efficiency and good value for money.