Hi Nidge,
As we usually travel out of high season, we usually just take pot luck when we get to the area we have chosen. However, this year we were going a little later than previously (late June/early July) and to a more popular area (St Remy de Provence), so thought we should book ahead. We were asked for a deposit and paid by credit card.
Next year we plan to travel in August and the site we fancy is very small. I guess they don't want the situationn that CC sites have in the UK, with people reserving a place and then not showing up! I can't say I blame them.
Jo