I haven't really met any well known people, but I have met a few voice actors - Yuri Lowenthal, Tara Platt, Vic Mignogna, Liam O'Brien, Troy Baker, Roger Craig Smith, Richard Epcar and Ellyn Stern. Everybody barring Vic were lovely people, he just seemed a bit arrogant.
Most famous non voice actor is Mark Owen. He's absolutely tiny!