The following web sites list positions available in the not-for-profit sector:
Idealist: www.idealist.org
American Society of Association Executives: www.asaenet.org
New York Foundation for the Arts: www.nyfa.org/opportunities
Chronicle of Philanthropy: www.philanthropy.com/resources
Council on Foundations: jobs.cof.org/home/index.cfm?site_id=11690
Council for the Advancement and Support of Education: www.case.org
Foundation Center: fdncenter.org/pnd/jobs/
NPO.Net (positions in Chicago metro area): http://careers.npo.net/jobs/
Dot Org Jobs: www.dotorgjobs.com