Patrick Warburton. Played David Puddy on Seinfield. Voice of Kronk in Emeperor's New Grove, Voice of "the Tick," was in Men in Black II, and dozens of other films and TV shows.
He wasn't the voice of The Tick, he *was* the Tick in the short-lived live-action series. However, he does do a lot of other voice work. And he does it well, I'll add, because so many do it poorly (especially the big name celebrities).
I think Patrick Warburton was the live-action Tick, and not the voice of the Tick on the animated show. I could be wrong, though.