For future searchers, mostly.
Didn't get a change to find any of the specific GF places that you can google, but here are some tips.
- Naturalia - this is a health food chain, all over Paris. They have a small selection of GF pasta, bread, crackers, etc. These were similar to the shelf-stable brands I see in my local grocery stores here. Didn't see any of the UDI style frozen bread, or freshly baked alternative breads that I've read about in other posts. Also has organic fruit and veg, and vitamins. The one we went to was just north of the Hotel De Ville (City Hall?) just across from the Isle de Cite.
11 Rue du Renard, just north of the Hotel De Ville Metro was the one that we visited. Just up the street from a "McDo" if you're looking for landmarks.
- Monoprix - target style store with clothes, makeup, and food. Food is located in the basement, take the escalator downstairs. Helpful if you have your own wheely bag/canvas bag to carry your treasures home. Has a VAST booze area if y'all are into that - you go through that area before you get to the actual food. Has a slightly more impressive selection of GF breads and crackers, and pasta, but still no frozen stuff. Prices more reasonable than Naturalia.
24 Boulevard Saint-Michel, just south of Notre Dame.
We also had printed out a San Gluten card and got a lot of use out of that. When we presented that to our waiters, it usually led to the chef coming out to chat with us. We would ask about a dish, and they would indicate Our, or Non, depending on what they could do, if they didn't speak enough english to counter our atrocious french. Didn't have any prolems in Paris with this method. Wife managed to get gluten poisoned when we had a 8 hour layover at Chicago O'Hare instead. Yay AA Admirals club.
I would highly suggest that you do what we did and bring along some GF food with you, until you hit dirt in Paris and can get ahold of a few things, in case you have to have something breadlike. Crepes are good, and if they use pure buckwheat (ask about sarrasin only flour) they shouldn't cause a problem, but all of the street stalls down north of Notre Dame used a mixture and we didn't chance it. There was one down by St Michael that was a creparie with actual bldg, not just a cart or front of the store and they weren't a mix flour and my wife loved it. There is a little maze of twisty streets just south of the Seine by St Michaels where we found a huge number of cafes, etc. Just remember your card, or speak reasonably fluent francais, and you should be good to go.
Please feel free to post other places you have found in your Paris travels, to help other folks plan their trips. All I ask is location addy for good, and the closest Metro stop be included as well as that will help narrow down for directions, etc.
Glenn in Tucson