Need more granular data than you can get from public census datasets? You may be interested in the Federal Statistical Research Data Lab at Baruch College. As the site states, "Federal Statistical Research Data Centers are partnerships between federal statistical agencies and leading research institutions. There are currently 31 Federal Statistical Research Data Center (RDC) locations. The RDCs are secure facilities managed by the Census Bureau that provide access to a range of restricted-use microdata for statistical purposes only. Researchers must have an approved project before conducting research at an RDC." Be aware, approval can take several months.
The U.S. Census Bureau portal for finding data on the race, ancestry, household income, etc. of populations from the U.S. Census and the American Community Survey. It is possible to create customized tables focused on a variety of topics, populations, and geographies.