The University of Chicago Library has a great page titled Health Statistics. Its contents include: What are health statistics?, Top five challenges to finding data, and A note on international data.
Data & Statistics (CDC)
Health, United States (NCHS, CDC)
MedlinePlus (U.S. Library of Medicine & U.S. Institutes of Health)
Pennsylvania: Facts-at-Glance (statehealthfacts.org)
The 2012 Statistical Abstract (U.S. Census Bureau)
International Statistical Agencies (U.S. Census Bureau)