To find a specific screenplay, search the film’s title in Omni. You may get irrelevant results such as a novel if the film is an adaption or titles that aren’t relevant to the film, but you can still browse the list for the screenplay.
However for popular films, you might have to do a keyword Boolean search, e.g.
“gone with the wind” AND (script? OR screenplay? OR “screen play?”)
If you don’t have a specific title, try this subject search: motion picture plays
Also try this keyword search:
For books about screenplays including guides to writing screenplays, try searching Omni with these subject headings: