To access your billing, you'll need to head over to www.reiconversion.com/account and log in using the email and password you signed up with
Once logged in, select Renewals & Billing on the left
Select your product
A popup box will appear on the right where you can manage your billing account.
You can upgrade or downgrade your plan, cancel auto-renewal, update your payment method and find your license key if you've just installed your site.