Here are most common Anti Virus Sites and Resources:
McAfee Anti Virus
Symantec Anti Virushttp://www.symantec.com/index.jsp
Trendmicro Anti Virus
http://www.trendmicro.co.in/in/
Quick Heal Anti Virus
http://www.quickheal.co.in/
K7 Computing
http://www.k7computing.com/en/
AVG Anti Virus
http://www.avg.com/in-en/homepage
F-Secure
http://www.f-secure.com/en/web/operators_in
Norman Antivirus
http://www.norman.com/no/index
Sophos
http://www.totaldefense.com/ca-antivirus-now-total-defense-antivirus
Virus Bulletin Ltd
http://www.virusbtn.com/index
FREE BitDefender Antivirus
http://www.bitdefender.com/solutions/free.html
FREE Avira Antivirus
http://www.avira.com/en/avira-free-antivirus
FREE Avast Antivirus
http://www.avast.com/en-in/index
FREE AVG Antivirus
http://free.avg.com/in-en/free-antivirus-download
FREE McAfee Antivirus
http://home.mcafee.com/downloads/free-virus-scan
FREE BitDefender Antivirus
Trendmicro Anti Virus
http://www.trendmicro.co.in/in/
Quick Heal Anti Virus
http://www.quickheal.co.in/
K7 Computing
http://www.k7computing.com/en/
AVG Anti Virus
http://www.avg.com/in-en/homepage
F-Secure
http://www.f-secure.com/en/web/operators_in
Norman Antivirus
http://www.norman.com/no/index
Sophos
http://www.totaldefense.com/ca-antivirus-now-total-defense-antivirus
Virus Bulletin Ltd
http://www.virusbtn.com/index
FREE BitDefender Antivirus
http://www.bitdefender.com/solutions/free.html
FREE Avira Antivirus
http://www.avira.com/en/avira-free-antivirus
FREE Avast Antivirus
http://www.avast.com/en-in/index
FREE AVG Antivirus
http://free.avg.com/in-en/free-antivirus-download
FREE McAfee Antivirus
http://home.mcafee.com/downloads/free-virus-scan
FREE BitDefender Antivirus
http://www.bitdefender.com/solutions/free.html
FREE immunet Antivirus
http://www.immunet.com/free/index.html
FREE immunet Antivirus
http://www.immunet.com/free/index.html
Microsoft Anti Spyware and Malware
http://www.microsoft.com/security/default.aspx