What is the best way to find camp sites in France and Spain?

If you are anywhere near the Midlands, have you thought of going to the NEC this week - tomorrow through to Saturday, inclusive. The Boating, Camping, and Caravanning Show is on and there are loads of stands with people from around GB and Europe handing out camp site information. When we were touring France, we picked up a book of Camp Sites from W.H. Smiths. Not only useful because it will list every camp site in every Departement, but will give you full info about facilities on the site and info about driving regulations etc. I don't know if you need a Camping Carnet, still, for example or if you need to buy yellow plastic covers for your headlights and carry a warning triangle; it's been quite a few years since I've taken a car to France. The AA can also advise. Another useful guide book is the Routiers Guide. If you've not driven before in France, beware that there are some differences such as Priority from the Right - you will find that you are on a perfectly normal major road and a car will shoot out in front of you from the right hand minor road. Brush up on your French, too, unless you are fluent speakers. French people will help you if you struggle with their language, but are inclined to most unsupportive if you don't try.

You would be well advised, particularly with safety in mind, to take advantage of the many quality sites throughout both France & Spain on which to park the vehicle at night. I've provided a link to a very comprehensive & informative site - http://www.campingeurope.com/guide.asp

A simple answer - every french town in the summer has a "Camping Municipal". Generally cheap, clean and basic. I wouldn't recommend any city centre but buses camp site to town are usually good. I take my van most years - I have never failed to find a spot.