We get a lot of questions at our reference desk about tax exemption, from the 1023-EZ form for small charitable organizations, to 501(c)(3) status in general. The San Francisco Chronicle recently published an excellent article with answers to some of these queries, in Q&A format. Make sure to scroll down to the third and final question, which is the one related to tax exemption applications.
Of course, you can always bring your questions about tax exemption, foundations, and nonprofits (or anything else philanthropy-related) to any of our reference librarians and they will help you find answers. Be sure to visit our library or to visit our online knowledge base.