Camping pointers and other advice for Europe

[Warthog]

Whilst saving continues for a Siberia trip in the future (a couple of years away, I imagine), we are taking advantage of my academic holidays to have a shorter jaunt around Europe. A trip in its own right, albeit shorter than the one above, but also quite therapeutic given that our next ride seems so far away right now...

As this is an interim outing, we are trying to keep it cheap so as not to plunder our hard earned savings too much. We plan to camp everywhere, and in this we may not have a choice, as we are travelling with the dog. It will also be a good test of the Ural's performance on the road (Alps might be interesting....)

Over 30 days, we plan to ride South-west from Estonia through
Latvia, Lithuania, Poland, Germany, France, Switzerland,

East through
Northern Italy, and Slovenia

Then North through
Hungary, Czech Rep, Poland, Lithuania, Latvia, and home.

So any pointers that spring to mind on camping in those countries?

Is free camping allowed in those countries?

Any other advice that is handy to know before arriving?