We have tried two gluten free places in Paris so far that we really like and can recommend.
One of them is a restaurant that is also vegan, Le potager du Marais, http://www.lepotagerdumarais.fr/
They serve tasty and nutritious plates both for lunch and dinner. Cost is around 10 – 20 Euros/dish. The service is very friendly and the waiter is charming and attentive, the best service since we moved here. A big plus for the home made gluten free bread that you always get with the food. The restaurant is in our neighborhood, only a five minute walk, so we are probably going to go there regularly during the year. Here is a picture of one of the delicious dishes they serve:
The other place is an all gluten free café called Helmut Newcake which is like heaven on earth for celiaks/people with gluten intolerance. They have many different beautiful French style pastries that melt in your mouth. On Sundays they serve brunch and Wednesdays – Saturdays they have lunch. You can find more info on: http://www.helmutnewcake.com