A few years ago we stayed in Peschiera del Garda which is on the Southern end of Lake Garda, it is a really nice and chilled out old walled town with various canals through it. I can't remember which campsite we stayed at but if you zoom in on Google maps you will see there are a few in short walking distance to the town centre.
I've been a few times. There are several campsites lakeside, between Torbole and Malcesine. Not stayed on them as we have either hotelled it or rented a villa in Navene.
Oddly enough villa rental ( usually small private houses) has worked out as cheaply as camping, on the occasions there have been 4 or 5 of us.
Which way you driving ? I've done France / Switzerland via Gotthard tunnel and on to Garda via Milan, but my favourite route for being quick and a lot more direct than it looks is Calais, cross the corner of Belgium, Koln, Franfurt, Munich, into Austria, then over the Brenner Pass, get off the A22 (?) at Rovereto Sud and head for Torbole, that's about 980 miles on the other side if I remember right.
EDIT; If you are into Mountain, or lake based sports and walking, then the North end of the lake is where it's at !