Roads generally are well marked, though as in most of Europe the route number is less important than knowing the line of cities through which you want to go to get to your destination.

Italians do tend to be a little mentally deranged when it comes to passing. Stay alert for being passed while going up hills, around blind spots created by horse-drawn hay carts, etc. Can be a little unnerving.

Driving in the cities is not all that bad. The biggest problem, to me, is driving into or outa major city. The routes, in Rome in particular, seem not to be well marked. You'll have much less trouble with a Perugia, Orvieto or Assisi than Rome, or even Florence.

I'm a nut about maps. Having a good map can be a lifesaver.

Get the most detailed one you can find in North America of the country, or region. (Typically at a scale of 1:300,000 or 1:400,000.) Use that for general planning. But you'll need more detailed maps (e.g. 1:100,000 or 1:200,000) once on the ground. Best detailed maps in my opinion are the Michelin 200 series which can't, for the most part, be found here. There are others and I'm frankly not familiar with Italian brands. You should be able to find the first one or two you may need in the airport on arrival, though, and you'll find others in small stores of one kind or another as you near the next are for which you don't have a detailed map.

Adventurous Traveler is an excellent source of maps. You'll find a selection of large scale Italy maps at http://www.adventuroustraveler.com/maploc.asp?location%5Fid=SAI&mscssid=V77APVHQM7S92M8V00AKHCNX42N8BDC3

Ed