In reply to j_duds: When I've driven I went to Dunkuerque on the lorry ferry, then down through Belgium, luxembourg, the germany, across the black forest (Pirmens somit or other) to Stuttgart, then Ulm, down to Neuschwannstein, Austria, to Innsbruck (remember to buy a motorway ticket though - theres a n ewsagents on the border where you can buy them, then over the Brenner. This takes you to the western side.
Guides - there is an excellent local guide in German or Italian which is streets ahead of the AC or the Kohler - you don't need much language as they are mostly good accurate topos. As for campsites theyare usually not that cheap but there's a nice one at the back of Pozza di Fassa and a good one in Corvara...