I am a student working on an assignment where I need to find and get
copy(s) of busines plan(s) previously used to develop a successful
movie/TV production company business. Do you have any suggestions on
where I can find such information?

Will something like this do?

Metro-Goldwyn-Mayer Inc. (the ?Company?) seeks to conduct its business
in the long-term best interests of its stockholders, consistent with
the tenets of good corporate citizenship. It seeks to achieve
consistently outstanding financial and operating performance by (i)
recruiting andretaining directors, officers and employees of proven
ability, high character and personalintegrity and (ii) requiring
strict adherence to a set of core values in the conduct of its
business activities. The business of the Company is managed under the
direction of the Company?s Board of Directors

http://64.233.187.104/search?q=cache:K_hQAJ7Lcb0J:media.corporate-ir.net/media_files/irol/62/62195/corpgov/CorpGovGuide2004.pdf+mgm+business+plan+pdf&hl=en&start=5