If you'd like your film to appear under our Movies tab - example: http://movies.eventful.com/limitless-/M0-001-000010444-8 - you must get your film set up with Gracenote (formerly Tribune Media Services) as they provide our movie data. (firstname.lastname@example.org) . Once your film is listed with them, it'll automatically be shared with Eventful.com - including trailers and showtimes.
But, if you'd like to use Demand to see where people want to see your movie - such as this film did: http://eventful.com/performers/msp-ski-movie-the-way-i-see-it-/P0-001-000237856-0 - all you have to do is create a performer page for your film. It's really quick and easy. Just login to your user account ( or create one, if you haven't already: http://eventful.com/join ) and complete the following form: http://eventful.com/performers/setup
Once you complete that, your film will be available for Demanding straight away. You'll also be able to add your trailer to your movie page under the "Videos" tab of your movie listing. As you schedule screenings, you can add those events to your performer page to keep a comprehensive schedule.