Help with Sponsorship Letter for Video Documentary

Hello,

I am with a small indpendent video production company in need of a little help writing a sponsorship letter. We are intending to produce a series of documentaries thar focus on today's family issues. We are wanting to help and educate the audience on the seriousness of "Internet Sexual Addiction". I will be sending letters to Phychologists, Counselors and other organizations. We are wanting to expose the problem with a solution in our documentary. Any help on how to address different organizations for sponsorship to produce this documentary will be grateful.

Thank you,
Wanting2Learn