To view your receipts or invoices for the purchases that you have made, you can use the main menu 'switcher' found on the top right-hand side of any page that you're logged into.

Next select Account from the dropdown options. Finally, on the left-hand side of your account page, select the Billing link where you can access the Manage Billing section and view all your invoice history.

If for any reason your invoice is not showing, then you can try searching your email for "[email protected]"