Have you checked it out?
Magestore Facebook login become free gift from this week when you buy any extension in Magestore.
http://www.magestore.com/magento-fac...xtension.html/
Magento Facebook Login extension allows visitors to sign up and log in your site via their Facebook account.
Use Facebook account to sign up without any other information required.
After signing up by Facebook, a new password can be released to make a separate account.
