There are thousands of immigrant rights organizations in the United States, and many thousands more around the world. A quick google search should turn up organizations in your area. Here are a few of my favorites:

Organized Communities Against Deportation (OCAD)

http://organizedcommunities.org

West Suburban Action Network (PASO)

https://www.pasoaction.org

Georgia Latino Alliance for Human Rights (GLAHR)

http://www.glahr.org

Puente Movement

http://puenteaz.org

National Day Labor Organizing Network (NDLON)

https://ndlon.org

Otros Dreamers en Acción (ODA)

http://odamexico.info

Immigrants Rising

https://immigrantsrising.org