palegray.net's Journal: Ways to build a Creative Commons based community?

My wife and I operate a small educational resources web site, under which we're trying to build a community of educators and parents who are willing to submit content licensed under Creative Commons style licenses. The objective is to ensure that member contributions are accessible to and freely usable by the largest audience possible, primarily educators and parents. I designed the site to include a donations system to allow people who find content useful to reward the author with a monetary donation of their choice, as an incentive for people to submit useful articles.

I'm at somewhat of a loss for how to really get the word out about this sort of system, without resorting to buying AM talk radio spots :). We don't have the budget for that sort of thing... my "day job" is active duty military, and my wife works as an EMS instructor. Wikipedia has the massive inertia factor working in their favor, and things are looking to get even better for their community with the switch to Creative Commons licensing for their content. What sort of communities are out there that could help us promote our ideas and build a community of education-centric folks?