Finding and Using Health Statistics is a free online class created by the National Library of Medicine. Geared toward students and librarians, it defines health statistics, identifies where they come from and discusses online resources for health statistics. This is a great place to start!
Please note: Many official agencies provide data sets available through the internet- check appropriate government (federal, regional and local) websites for individual offerings.
PolicyMap is a fully web-based Geographic Information System (GIS) and mapping product. Data includes demographics, home sale statistics, health data, mortgage trends, school performance scores and labor data like unemployment, crime statistics and city crime rates. A complete list of GIS data available can be found in their data directory.
A multidisciplinary data repository covering business, economics, finance, social sciences, demographics, public health, and more. Contains many tools for exporting, comparing, analyzing and visualizing the datasets.
Many health-related agencies provide data sets available through the internet. Check appropriate government websites(federal, regional and local) for individual offerings.