I've read that when one arrives in Italy, one should buy a phone card to use for local calls. Are the calls strictly local to each city, such that I would need a separate card for Rome, Florence and Venice?

The Europa card, which gives you 200 minutes for 5 Euro, is good for international, local and other cities in Italy. There is a number on the back to dial for English. Very easy. If you're going to be calling a lot, there is also a 10-Euro card.

As far as I can tell, the same card can be used for both local and long distance calls. Some are like US calling cards and can be used form any phone. For public pay phones you may need the card that is inserted into the phone (after you've torn off one corner of the card).
From a hotel or private home, you would need a card only for long distance calls.
This may be helpful:
http://slowtrav.com/italy/instructio...lic_phones.htm

I made a both a call back to NY from Rome and a local call in Rome from a phone booth and did not have to have a card that inserts into the phone. I just dialed the number for English on the back of the Europa card.

Thank you!

sometimes you have to buy a card that allows international calling, some are for Italy only. Some international cards do not allow calling the USA and are for Europe only.

You may have to specify which one you want.