ICPSR: Inter-University Consortium for Political and Social Research This link opens in a new window
From their web site: "An international consortium of more than 700 academic institutions and research organizations, ICPSR provides leadership and training in data access, curation, and methods of analysis for the social science research community. ICPSR maintains a data archive of more than 500,000 files of research in the social sciences. It hosts 16 specialized collections of data in education, aging, criminal justice, substance abuse, terrorism, and other fields.
ISU has a membership, but you must create an account to access the data.