God, I'm so old, I can barely remember some of them. I've seen many dozens, but of the celebrities I've "met", meaning anything from shaking hands and saying "hello I like your work" to a longer conversation or extensive interaction, here are some:
Mary Tyler Moore
Cuba Gooding, JR
Paul Simon (the senator, not the singer)
I will probably think of more, and add them later.
(And since I arleady know all the circumstances and details of these encounters, I hardly need to list them to satisfy my curiosity