In reply to Emma:
Just to add our experience - we went in Aug last year (and got lots of advice from this parish in advance, search the threads).
I could not book camping in advance so hoped to just turn up and find a spot. We targeted Cortina as a base, and found that all 3 campsites in/south side of the town were full up. In particular we didn't like the look of Camping Dolomiti - v sardine-like and the reception stank of incontinent old men.
We ended up heading north and went to Camping Olympia - managed to get pretty much the last free spot in the campsite - so we were lucky, but it could have been a camp-in-the-trees job.
In short - hard to book, need to have a hit-list of campsites to drive around and find somewhere - and don't go in mid August! If I went again, I'd aim for sept.
Nick
Post edited at 09:30