In reply to Charlie Zephyr Booth:
Camping Les Près à Grez-sur-Loing is okay. It is more to the south closer to l'Elephant and has some places for campers. No too far away from the A6 autoroute.
I would say stay away from La Musardière à Milly. Too many wild cats and high price and hardly any or no guardian active. But the boulangerie at Milly are better (as one can see Madame Meuniere, the proprietor/owner, is visiting the boulangerie at least twice a day).