Just come back from France where I have our boat.
If you go to the http://www.angloinfo.com they have covered this in detail
Data OK but GPRS you will need a monthly contract phone
Used SFR (in Corsica) just last week to connect to the internet using AOL. Very slow connection but I think that was more AOL in Corsica than anything else. Now using WIND in Italy which is great with AOL.
David