A non-for-profit organization does not have to be a corporation. It can be a trust or an association. First you need to find out the identity of your organization. Check out state registry for sure. If this is a corporation, then check the bylaws to see whether it gives your access to the books. The IRS requires NPO's to file full disclosures and make them available to public for three consecutive years. Check the organization website to see whether you can find the disclosures somewhere.