If you upgraded to Pro or the Company plan directly through your Marvel account, you can find your invoices online:
Head to my account > billing > invoices
This will give you access to all previous invoices from your account and allow you to download it as a PDF file. Unfortunately it's not currently possible to automatically send invoices to you by email each month.
If we bill you by invoice, you can get a copy of your invoice by contacting your account manager or emailing us as firstname.lastname@example.org