Association of American Colleges & Universities: AAC&U has many publications on the topic of equity in higher education. For starters, check out this list of resources and the report A Vision for Equity, which contains the results from AAC&U's Project "Committing to Equity and Inclusive Excellence: Campus-Based Strategies for Student Success."
National Association of Diversity Officers in Higher Education: NADOHE serves as the preeminent voice for diversity officers in higher education.
National Association for Multicultural Education: NAME is a non-profit organization that advances and advocates for equity and social justice through multicultural education.
National Coalition Building Institute: NCBI is an international leadership organization that provides training in diversity, equity, and inclusion (DEI) in community organizations, K-12 schools, college and university campuses, corporations and law enforcement.
American Council on Education: ACE has pulled together news and resources on their Campus Diversity and Inclusion page.