I have to second the recommendations of the Midwest Gaming Classic, especially if you're into video gaming as well. I got to play Goin' Nuts there last year, one that I hadn't seen anywhere else. Caveats: hope you're comfortable with elbow to elbow crowds, and during general admission hours there will be waits for games.
Also featuring vids, I'd be remiss if I didn't recommend California Extreme (CAX). Big show, great atmosphere, and the first place I've been able to play stuff like Big Bang Bar, Capcom's Kingpin, and the Atari protos. Rare and proto video arcades you aren't likely to find anywhere else, too.