You asked about needing an International driving permit in Italy. I
just rented a car from Avis in Florence and only needed my US driver's
license. I got a good weekly rate from Travelocity, think it was about $230
US for a mid-size Fiat. The car was terrific, handled well through the
mountain roads in Tuscany as well on the AutoStrada. It had A/C, a 5-speed
manual transmission (automatic is difficult to find) and was a diesel. I
was concerned at first but the agent said diesel gas was easy to find,
cheaper than gas and better fuel economy. She was correct on all points.
Have a great trip and drive defensivly.