Where Can I Look To Find A Good Non-profit Job In St. Louis?

I am graduating with a degree in public relations and a minor in non-profit administration with the aim of working in the non-profit sector in April. I am already looking for a job since I realize the market is bad and there is a lot of competition out there. However, I am having a hard time finding job postings relating to the non-profit sector. Where should I look besides the obvious places (Monster, Yahoo, the Rome Group, etc)?
Thanks!