If you are based in the UK and are fed-up of paying through the nose for international calls to Italy and elsewhere, then it may be worth visiting Budgetcom.  From this site you can get low-rate access numbers to call Italian landlines and mobiles, as well as just about every other country in the world.  Currently it costs just 2p per minute to ring an Italian landline and 25p per minute to an Italian mobile from the UK - great value - but please check up-to-date rates on the web site before you make a call.