The best way is to talk to professors, read journals and keep up with current events and see who is releasing information on different types of research . Find organizations that do research in the area you are interested in. If you majored in sociology, my job hunting showed me you need to know 2 things:
If this is not an option, you can use this technique. Goto YAHOO (Regions - U.S. States) and pick a state that you believe has many research institutions or is an area where you would want to live. Pick a city where they might be located (the 2 major research locations are below) and under the yellow pages search box, type "research" and/or "organizations"
Many newspapers are online so you can search their classifieds. Again, I would recommend the Washington Post or the New York Times. They both offer research sections.
You can also do a comprehensive newspaper search with CAREERPATH.com. Click on "find job by newspaper", click on topic (research) and then select different newspapers.
A web site called POLICY.com also offers a good list of research organizations or be a true non-academic sociologist and work for a non-profit organization. A very good starting point is IDEALIST.org.
Good luck.