General
Craigslist
http://philadelphia.craigslist.org/
Monster.com
http://www.monster.com/
Careerbuilder.com
http://http://www.careerbuilder.com/
Local
Philadelphia Inquirer (also lists careers fairs and events and contains articles and other resources)
http://www.philly.com/philly/jobs/
Philadelphia Public Schools
http://webgui.phila.k12.pa.us/offices/e/ee
Nonprofit
Idealist.org
http://www.idealist.org/
The Nonprofit Center, LaSalle University
http://www.lasallenonprofitcenter.org/resources/nexus.php
Universities
University of Pennsylvania
http://www.hr.upenn.edu/Jobs/
Temple University
https://hospats.adminsvc.temple.edu/jobs.htm
Drexel University
http://www.drexel.edu/hr/jobs/index.html
Government
City of Philadelphia: http://www.phila.gov/personnel/announce/index.html
State of Pennsylvania Civil Service:
http://www.scsc.state.pa.us/scsc/site/default.asp
Federal Government: http://www.usajobs.gov/