The New Immigrant Survey (NIS)
http://nis.princeton.edu/index.html
The New Immigrant Survey (NIS) is a nationally representative multi-cohort longitudinal study of new legal immigrants and their children to the United States based on nationally representative samples of the administrative records, compiled by the U.S. Immigration and Naturalization Service (INS).

The Latin American Migration Project (LAMP)
http://lamp.opr.princeton.edu/default.aspx
The Latin American Migration Project (LAMP) is a collaborative research project based at Princeton University and the University of Guadalajara. The LAMP was born as an extension of the Mexican Migration Project (MMP). Data from Puerto Rico, the Dominican Republic, Nicaragua, Costa Rica, Paraguay, Peru, and Haiti are available, and can be downloaded from the website.

The Mexican Migration Project (MMP)
http://mmp.opr.princeton.edu/
The MMP is a multidisciplinary research effort between investigators in Mexico and the United States. The MMP randomly samples households in communities located throughout Mexico and collects basic information on each person's first and last trip to the United States. It also includes detailed series of questions about the last trip northward, focusing on employment, earnings, and use of U.S. social services.

The European Social Survey (ESS)
http://www.europeansocialsurvey.org/
The ESS data cover over 20 countries..The interviews cover questions on immigration, citizenship and socio-political issues.

Murray Research Data Archive (Diversity Samples)
http://dvn.iq.harvard.edu/dvn/dv/mra/faces/SearchPage.jsp;
jsessionid=e012a9946b60a391f66bd9dadd64?mode=1&collectionId=4
The diversity samples of the Murray Archive contains a collection of cross-sectional and longitudinal data sets with detailed individual level indicators on race, ethnicity, and migration.

International Migration Data Sets (made available by F. Docquier, UC Louvain)
http://www.ires.ucl.ac.be/CSSSP/home_pa_pers/Docquier/oxlight.htm
The data provided include migration flows disaggregated by educational attainment, age, and gender as well indicators of the medical brain drain.