Try http://www.petersandmay.com they are shipping my dismasted and damaged Contessa 32 overland from Massachussetts to New Jersey and then shipped to Southampton. This is due to take place beginning of April, so as yet can't say how it went. The price seems quite reasonable though after getting quite a few other quotes.
try dock express, they do several trips to / anf from the med each month. The boats are driven into the containership into a cradle, secured by divers and then when all the ships are loaded the water is pumped out.
Dock Express
Paseo Maritimo
Edificio Torremar
07015 Palma de Mallorca