Downloading an Invoice
Zettagrid invoices for most services every month. When logged in, you can see an invoice list, including amounts, due dates, open balances, and more from the Billing->Invoices page.
Choose Billing
Click Invoices
Click View (Shows Invoice in your Brower) or Save (Saves a PDF onto your computer)
If you have outstanding invoices you can Pay
Use the other Tabs view historical invoices or Account History which will show invoices, receipts and credits.