My wife and I are going to France in a few weeks. She is a vegetarian, but does eat dairy. We are planning on driving around a bit, and expect to spend time in Paris, Lyon, Montpellier, and Bordeaux. We're looking to have a couple of "special" meals (don't know if we can afford L'Arpege), other than that, any help would be appreciated.
We recently had a wonderful dinner at Lasserre in Paris and were impressed with what seemed to be several vegetarian dishes on the menu. There was a special section of the menu with those dishes, though I don't remember what they called it. You may want to walk by there when you get to Paris and look at the menu (and the prices) before you decide
I now eat seafood but when I started traveling to France 11 years ago, I was a vegetarian and I happily lived on bread and cheese. In my opinion, it's not easy being a vegetarian and dining out in France especially outside Paris.
Anyhow, here is a website that might be helpful:
For your special meals, there are restaurants/chefs who are willing to provide a vegetarian meal especially if you book ahead and make a special request. I think Le Cinq does vegetarian tasting menu. Some French people consider seafood to be "vegetarian" so it's better to be specific about what your wife does not eat including stock made from animals.