Sourcebook of Criminal Justice Statistics
http://www.albany.edu/sourcebook/

U.S. Department of Justice -
Bureau of Justice Statistics
http://www.ojp.usdoj.gov/bjs/

National Criminal Justice Reference Service
http://www.ncjrs.org

National Archive of Criminal Justice Data
http://www.icpsr.umich.edu/NACJD/

Criminal Justice Links
http://www.criminology.fsu.edu/cj.html

FBI Uniform Crime Reports
http://www.fbi.gov/ucr/ucr.htm