There are quite a few article databases that may be helpful. Choosing the right one depends mostly on your topic/ focus. Databases below are divided into broad areas. Try to think about which one (or two) your topic fits with.
Mental illness: depression, substance abuse, suicide, anxiety
Sociological codes in prisons: power structures, racial groups, relationship building
Rehabilitation of prisoners back into society: educational programs, counseling efforts, career counseling, outside support systems
Motherhood and imprisonment: effects on children and their well-being, effects on mothers, relocation complications
Sexual assault: rape as a form of control/ power, pregnancy within prison, guard- prisoner sexual assault and conviction