In order to add referers to your site there are three things you need to do:

1) Turn the logging on by going to the Blog Configuration Document - Logging Tab - and then selecting "Yes" for Log Referers.
2) Insert the DXTag "<$DXReferrers$>" into your Site and Document Template where you wish them to be displayed.
3) Ensure there is an 'Anonymous' entry in your blogs 'ACL' - this should have Author rights with the ability to create Documents