WebJunction

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

This freely available data warehouse contains data sets covering corrections, courts, crime and delinquency, the criminal justice system, hate crimes, homicides, international crime, police, victimization, violent crimes, and several other areas. To download data public users may create an account with the system, or download anonymously.

 
National Criminal Justice Reference System
http://www.ncjrs.gov/

The NCJRS collection covers the broad subject area of criminal justice and its related fields of study. Broad topics such as corrections, law enforcement, drugs and crime, juvenile justice, and crime victims are comprehensively covered. Similarly, more focused subjects within these broad topics are also covered such as technology in law enforcement, domestic violence, drug policy, and juvenile violence.  Full text publications can be browsed and searched from the publications page. A separate resource, the NCJRS Abstracts Database contains summaries of nearly 200,000 publications housed in the NCJRS collection. Many of these publications, however, are not published by the U.S. government, but by commercial publishers. All full text publications from the publications page are also indexed in the NCJRS Abstracts Database. The database has a useful online thesaurus of controlled vocabulary terms for more precise searching.

 
National Sex Offender Public Registry
http://www.nsopr.gov/

The NSOPR is a cooperative effort between U.S. state agencies that host sex offender registries and the federal government and includes information on individuals who have been convicted of a criminal offense against a victim who is a minor, or a sexually violent offense.  It can be searched by name, zip code, county (if provided by state), city/town (if provided by state), or state (one or multiple).