Search a list of resources for prospective buyers looking for movie ideas. The Hollywood Creative Directory contains a list of all of the production companies in Hollywood. Also, search the classified sections of industry trade magazines such as Variety, The Hollywood Reporter and Backstage, as well as Internet classifieds. There are also various internet script/idea movie market websites.
Contact a production company, or producer, that is looking for story ideas. Once you have found someone interested, you can prepare your materials.
Write a logline. This is what's known is the industry as a one-sentence description of your story.
Write a synopsis of your story. This expands on the logline and is usually a one-page document that summarizes your story as succinctly as possible. Most Hollywood movies are based on a three-act structure, with the beginning, middle and end clearly explained.
Write a treatment/outline of your story with as much detail as possible. This is the blueprint for your movie but is much shorter than an actual screenplay. The treatment should be approximately 12 to 25 pages.
Protect your work. Register everything with the Writer's Guild of America West or East, and copyright it.
Download and sign a release form if one has not been provided to you. This is to protect you and the prospective buyer from legal claims.
Mail your materials to the producer/prospective buyer and wait for their response.