I spoke to a really friendly, cheerful and helpful lady today and wanted to know if there's any way of passing positive feedback on her to her supervisor.

I didn't get a receipt number but I do know her name - if I quote my centrelink number would that show on my file who i spoke to? If so, how do I pass on my feedback?
It's worth a shot - just call and explain what you'd like to do and ask to speak to a supervisor. It'll get back to her, and speaking from experience on having worked as a phone consultant (not for c/link though) it really really makes your day