I've actually been to Tuscany, briefly, we mostly stayed in the city of Florence and didn't get out into the countryside, but I think I can help.
Columnar junipers like "Skyrocket" would work.
Rock pines, or Tanyosho Pines. Work work.
I saw ornamental Agave's planted all over Italy, but that is obviously not native.
Of course grapes.
Lavender is good.
Can you grow olives? Lemons?
http://www.gardeningforums.net/galle...ry.php?cat=503
Those are my garden pictures from the trip.