I'll be going to Italy in September also. I got the SIM unlock code from ATT, and I plan on buying a SIM once I arrive (I've heard it's much cheaper that way). Then I'll just phone home and give family my italian number.

For GPS, I plan on using TomTom and allready have the Italy maps loaded on my storage card.

The only thing I"m a little vague about is how data charges will work on a pre-paid italian SIM card.