thanks for the link :) Their prices are a little steep (3 nights in May is 172 pounds) :(

We are planning on moving around quite a bit, so now we're discussing maybe bringing 2 small tents from home. The boys have a lovely North Face 2 man tent that weighs only 5 pounds. If we invested in another 2 man tent we'd be lightweight and good to go. We are also looking at a "family" tent (the Twister 4 which looks exceedingly easy to set up and take down and weighs only 12 pounds).

blessings,
travelling mom

A couple things... In France most towns have municipal campsites.. usually not far from the shops etc.
When on teh road, at 12 noon you will often see waste ground with loads of lorries parked near some nondescript building. This will be a 'relais' where you can get a genuine french 3 or 4 course meal for around 10 euros ( including wine) They are almost all exceptional value.

Euro camps etc..
 

The Eurocamp type facilities can be great for families, but they book quick and are sometimes costly dependant on location and time of year.

Campsites in europe are far more common than here in the UK, and you shouldnt have any troubles finding one, just ask at local store's or tourist information centres.

Great tip about the truck stops, they are cheap and do great food.

Be warned that most airlines are getting very strict over excess baggage and they charge a fortune for extra, due to rising costs of fuel.

I honestly think that as long as you hit a major town in german you should be able to locate a camping shop and equip yourself pretty well. The other option if you know your first nights destination is to post your tents across to the hotel in advance of your arrival. Most reasonable hotels will hold packages for patrons..

I had a list somewhere of Euro Biker Campsites, that were motorcycle friendly and usually a great place to stop, great friendly atmosphere.
I will see if I can find it somewere.