I just found out about TCM's film festival in Hollywood at the end of April: http://www.tcm.com/festival/
I definitely want to go. They are going to play Top Hat, among other films that would be fun to see. They are screening at Grauman's, the Egyptian, and other venues.
It's pretty expensive though, and I don't know if you can pay for individual tickets because I've only seen the passes so far.