In Paris you have :
DUPON
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You will find their address (they have two, but the main is in montmartre) in the site but they also have a little space where you can give your films for processing (and everything you can imagine) called Espace Dupon Bastille located at 42 rue St-Bernard in the 11th district, which is not listed in the website
IMAGINOIR
http://www.imaginoir.fr/
8, passage Montbrun Paris 14e
PUBLIMOD'PHOTO
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16 rue du Roi de Sicile Paris 4e
All three are professional labs and will give you the best quality, especially if you are looking for black and white work (dupon and imaginoir are specialists). But they all are quite expensive.
A less expensive lab is NEGATIF+ (106, rue Lafayette Paris 10). Would recommend it for color but not for b&w (not at all). They also have a good supply of films. They are good but not as good as the labs I gave earlier (but they are also a lot more affordable).
Now for suppliers :
PROPHOT
37-39 rue Condorcet Paris 9
Jipé Labo
14 and 9 rue Condorcet Paris 9
But when it comes to buying films I go to them only when I can't find what I want at Negatif+. Not that they are not good, but N+ is just closer from my home

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A good place to go when you're looking for photographic supplies is the Boulevard Beaumarchais near Bastille. It is filled with plenty of photographic stores. I can recommend AMC LABO, AMC Photo, Cirque photo..
Voila !
It's all I can think of for the moment. Hope it's helping you
Arnold