sorry, I cannot give you any information about campsites near Ulm except a Garmin file with campsite waypoints. However, not being a full member, I cannot post the file here, I'm afraid.
If you want this file, let me know and we'll find a way to send this file from D to UK .
We are thinking of visiting ULM to go to the local Legoland and reckon on staying a a Youth Hostel. Never stayed in one yet but have booked into a Youth hostel situated in a Castle in Bacharach and looking forward to it.