Reports and Papers from Think Tanks and Researchers
Provides online access to abstracts and full-text articles on public policy research and analysis from think tanks, university research programs, research organizations and publishers. Much better results than searching Google.
James McGann at the University of Pennsylvania ranks public policy organizations each year. The report organizes ranking by the world and by region in addition to a ranking by area of research.
Mathematica Policy Research
A research firm focused on public well being in the areas of education, family support, health, and labor. Many of its reports are available for you to use on the company's web site.
Other companies providing research services to the United States government also make many of their reports available to the public. See Westat, MDRC, and RTI International as examples.
This organization makes conference papers searchable and provides full text access to many of them. SSRN collects conference papers, journal article pre-prints and working papers in the social sciences. This is a good place to find very recent material.