Besides local legends NIL8, my first big show was at the state fairgrounds on a dirt ring mostly reserved for horse shows. It was The Offspring with The Vandals and Lunachicks. I usually omit the Offspring when talking about it.
Wait, does "Weird" Al count? I think I saw him when I was very young. I also might have seen the Beach Boys on the Kokomo tour (at the aforementioned fairgrounds), but obviously that was not so memorable.