To see your print credit statement go to 'settings' and then to 'referrals'. You will see the credit you have earned as well as the credit used against print orders. Also you can see where the credit earned is being earned, i.e. against which referrals.
Looking further down the page you will see the land you have helped to protect as a result of your referrals.
Also you can see summary versions of both of these things on the dashboard of your account.