What section of your account were you looking in for these invoices? After taking a look, I was able to locate them and would be happy to help point you in the right direction! Your account invoices can be found by clicking the name in the upper-right and selecting My Account in the drop-down.
Under My Account is the option to click "View Statements" or "View Billing Activity/Statements" in the bottom-left hand corner.
You will then be brought to a page where you can view, print, and email the invoice based on the time period you are interested in.
Where you able to view your invoice following these directions?