1. Centers for Disease Control & Prevention (CDC), National Center for Health Statistics (NCHS)
ABOUT: publishes annual data on deaths from different causes in the National Vital Statistics System, but effort takes 18 months to collect, compile, verify & release these statistics to the public

CDC Death Statistics: Suicide and Self-Inflicted Injury
http://www.cdc.gov/nchs/fastats/suicide.htm

CDC Death Statistics: Assault or Homicide
http://www.cdc.gov/nchs/fastats/homicide.htm

CDC Death Statistics: Accidents or Unintentional Injuries
http://www.cdc.gov/nchs/fastats/acc-inj.htm

CDC Death Statistics: All Firearms
http://205.207.175.93/HDI/TableViewer/tableView.aspx?ReportId=71

2. National Violent Death Reporting System (NVDRS)
ABOUT: Uses data from 16 states, representing roughly 26 % of firearm deaths in U.S.
URL: http://www.cdc.gov/violenceprevention/nvdrs/

3. National Crime Victimization Survey (NCVS), Bureau of Justice Statistics (BJS), Department of Justice (DOJ)
ABOUT: NCVS collects data on reported & unreported fatal & nonfatal violent crimes against persons 12 years of age or older
URL: http://www.bjs.gov/index.cfm?ty=dcdetail&iid=245

4. Uniform Crime Reporting (UCR), Federal Bureau of Investigation (FBI)
ABOUT: Uses crime stats annually from 17,000 city, county, & state law enforcement agencies that submit data voluntarily
URL: http://www.fbi.gov/about-us/cjis/ucr/

5. National Electronic Injury Surveillance System (NEISS), U.S. Consumer Product Safety Commission (CPSC)
ABOUT: provides data for nonfatal firearm injury. NEISS data are collected from a sample of 91 hospitals in the U.S. by the Consumer Product Safety Commission. No geographic data is provided.
URL: http://www.cpsc.gov/en/Research–Statistics/NEISS-Injury-Data/

6. Bureau of Alcohol, Tobacco, Firearms & Explosives (ATFE)
ABOUT: collects limited data on gun manufacturing & sales
URL: http://www.atf.gov/statistics/index.html