Hi William,
I can surely tell that I live in the North of Italy. But is quite a broad region, can you specify where exactly you live? Eg. if you live in the Po plain, in the Appenines or Alps, if you live close to the sea.
I live in Reggio Emilia and temperatures go below -17 C with 50 to 60 cm of snow. I also work in a farm during the spring/summer months, the farm is in the appenines above 700m above sea level, that makes for a -25C temperature with 2 to 3 m of snow.
So, what I suggest is to look here:
http://www.agraria.org/
and start gather data for your specific microclimate, as Northern Italy has got so many.
I grow to name a few: apples, pears, persimmon, quince, medlar but also pomigranate, figs, mulberries, cherries...
So, I think you can also have a look at
http://www.agroforestry.co.uk/seedorders.html, this site gives you enough information to try new plants.
Precipitation is also a big factor, an beware of the diseases of plants. You can import seeds easily from the uk, but not from the us, and I really think you can source plants in Italy easily, especially in nurseries in Tuscany and in nurseries around Garda's Lake.
Good luck!
Elena