Hello all who've given advice or made any contributions whatsoever. Here's a little update, if you care.
Right now, I'm still trying to figure out who exactly to contact at my school, but I'm keeping this idea amongst students at the moment, and using SGA to find the appropriate contacts. I haven't met any real opposition thus far, so that's good. Hopefully it can all work out, but if I can't get a real sorority going, maybe I can at least start a student interest group (Facebook recruitment for that, I guess) and try again next year. I don't think I'll give up until I get some semblance of what I want...
I can be quite persuasive.