Hey PBTannie
Surcharging is automatically enabled when you first set up online payments. Options to change these settings to your preferences can be found in your settings, this page has instructions and explains how the surcharging and fees work. How online payments are recorded in MYOB and what to look for if your payments aren't auto-matching to a transaction can be found here. Hope that helps.
Easiest way to contact the team for any questions about online payments would be to raise a support request via My Account, the last link in my last response also includes other contact options. You also have your AccountRight Priority support option available as well for other questions using AccountRight.