RhetoricalAnarchistI think Strongsuit makes an important point. We have so many great writers in the community, could we put together a large document as a collaborative effort and send it as a letter to various organizations looking for sponsorship. It would have to include our goals, reasons why we should be sponsored, and a strong showing of a unified community supporting the game. Obviously some of this work would fall on the shoulders of a select few committed and organized writers, but we could also include testimonials and statements from everyone who posts one, almost like a petition. With any luck, somebody would pick us up, although the worst thing any organization can do is simply turn us down.
What you're basically asking is for the community, a collection of people who have a desire for a specific thing (in this case TF2), to make a business proposal. What you're missing in this situation is that a community is not a business and cannot function as one, thus by asking an organization for this sponsorship and/or money they're going to respond 'to who?' Are you going to have them mail it to Valve or something? I don't care how well certain people within the community could write the idea in itself is flawed.
Have eXtv / TF.TV / Vanilla.TV / BlackOutGamingTV 'hire' one of these writers and do that sort of job for them. Have them write up that business plan as they're an actual business who could sort of pretend that there would be a ROI on any sort of funding put forth. Although I'm pretty sure that most of those organizations have already tried all that they can to work on getting certain sponsors, seeing how much this community talks about 'needing money.' Unless you're going to approach an organization that's setup to run tournaments in itself and host the tournament ect., I don't see where you're going with this.