This is, of course, a big subject. Here are a few links that may offer help with understanding the field or some specific question:

* Nonprofit Resource Center
* The NonprofitExpert.com
*Governmental and Nonprofit Accounting by Robert J. Freeman, Craig D. Shoulders. Order this book from Amazon.com.
* Improving Disclosure and Transparency in Nonprofit Accounting by Gerald Aranoff, Ph.D. CPA. Published in Management Accounting Quarterly Spring 2003.