In Incident Management, in the Survey Task dialog workflow component before the end component in the Customer Confirm Resolution model, theres a comp labeled "Send Incident Survey Email" in the start model.
Also, in the Customer Confirm Resolution model, in the Have Customer Confirm Resolution dialog workflow component, we send an email in the start model. This comp is labelled "Send Incident Resolution Email".
Is this what you're looking for?
I'm unsure what version of SD you're looking at, but this looks like the right place.