Pauline google " Guida Camper AREE DI SOSTA" for the up to date info it's published by Belletti and is quite expensive but well worth the money, look on fleabay for a newish one but I have a 2007 edition which will no doubt be well out of date which you can have for reference if you want it.
Been 3 times to Italy and really do want to go again so I can drive the Amalfi coast road, cannot be done in a m/h but I would hire a car and travel it, the scenery is stunning.
There is a FICC rally in 2015 at Sorrento which would be a good introduction to Italy and the FICC rallies are excellant.