My first concert was Simon & Garfunkel at the SCG. (I think it was 1983, but there's currently some animated discussion on Facebook about the actual date.)
A bunch of us from High School went together, with a parent chaperone. We were such nerd fans that we right down the front swooning at our idols the whole time. We were screaming out for them to play For Emily, and eventually Paul turned and asked the band about it. Shrugging, he looked back to us and said off-mike that they didn't know it any more. So we yelled for Feelin' Groovy instead, and got it.
In an interview on Australian radio later in the week, they made a reference to the crazy girls at the front at the Sydney concert. We were so proud.
Update It has been convincingly asserted that it was February 5th, 1983. So we were all fifteen-ish. That makes it thirty years ago in a couple of weeks. There's talk now of us all getting together for a reunion, which wouldn't have happened if findery hadn't prompted me to ask the question. Noice!