Hello!
I can really share your liking for Montmartre; it is really something special. I have spent some beautiful evenings there where street musicians played all night long for the entire satisfaction of the tourists and the parisians too as no one dared to stop them. There is such an atmosphere with the lights and the terrace on the sidewalks so lively.
I have been to many, many hotels in Paris for business and leisure as Paris is definitely my favorite city. Unfortunately I don't know any hotel in the area of Montmartre.
But I can recommend to you a few good hotels that I have enjoyed tremendously.
One is hotel de Varenne, very close to the Esplanades des Invalides. I like the charm, its quietness, its staff so courteous and helpful and on the top of that its beautiful although tiny inside garden with its flowers, plants and trees.
http://www.varenne-hotel-paris.com/There is another one that I like also very much and this is hotel Concortel. This one is just around the corner to the square la Madeleine; I was there with my parents this time and of course it was just perfect for them, close to Laduree, Hediard, Fauchon, Grand Magasins, Galeries Lafayette, etc. I was particularly pleased with the hotel manager who is really dedicated to make your stay a real pleasure.
http://www.concortel-paris-hotel.com/I know more hotels that these 2 so if you want more advice let me know.