As to how much you net after all your expenses, time and hassle... I'm guessing not much. If you are looking to make some money on the side you'd probably do better flippin burgers at McDonalds. I doubt that is why collectors do it though
German poster collector and seller Karlheinz Borchert has published a book on Japanese movie posters: http://www.postertreasures.com/artof3.htmlIt's not genre-specific so you get a nice overview of Japanese posters in general.Armin