Hi Francesca,
Yes there are tarot and esoteric shops in Paris. As a matter of fact, I think new age has become more popular in the last few years, more than I remember when I was living there. Here are a few addresses (although I don't remember seeing books in English, I'm not even sure the owners speak English):
La Table d'Isis
3 rue Fontaine
75009 (9th district)
The metro is: Notre-Dame de Lorette
Gibert ésoterisme
23 Quai St-Michel
75006 (Metro St-Michel)
Librairie Inconnu
84 rue du Cherche-Midi
(Metro: Sèvres-Babylone)
Cygne d'Etang
102 rue Charonne
75011 (11th district)
I've never been to the last one. I don't have the phone numbers either. I looked up the metro station in a book whre you find all the streets. You can find some more information in the French white or yellow pages on the web.
I hope this helps,
Aries.