Dodo,
Moodle core supports the two followiing payment methods, which you can find by doing a search for enrollment in the Moodle documents section.
Authorize.net
http://docs.moodle.org/en/Authorize.net_Payment_Gateway
PayPal
http://docs.moodle.org/en/Paypal_enrolment
Enrolment
Payment Method
This discussion has been locked so you can no longer reply to it.