There is a large concentration of Indian/Sri Lankan restaurants in the Passage Brady, in between Saint Denis and Sebastapol, just north of Grand Boulevards.
Ewelinka, you really are a restaurant lover - you ask questions about all kind of restaurants. In regards to an Indian restaurant, here you go Kastoori 4, place Gustave Toudouze, 75009 Paris Ph 0144530610
There are actually quite a lot of Asian restaurants in Paris, and you'll be surprised to know that there is a "strip" in Paris which is lined with some Indian restaurants all serving authentic and delicious Indian cuisine. you can find it at Strasbourg-St. Denis area. the street has about 10 to i think 15 Indian restaurants. They offer good seating and most of the restaurants are open even until midnight! so if you're craving for delicious and cheap Indian cuisine late in the evening, you can go ahead and visit this place..