Joe90,
It's not as simple as that I'm afraid...
The camping areas seem to be all lumped together as Aire d'accueil, camping or lay-by. Some have showers, some don't. If you have tickets for camping, let us know which site, and someone will let you have details of what facilities you can expect. If you don't have tickets, then have a word with the immediate members of your family, and see if any of them would mind being sold. If any of them are particularly unusual, contact me first.
Good luck
H