If you're like 99% of Americans you have no idea where Butler is located, let's be honest here. I'm a sports fan, but even I had to Wiki it while creating this map (and that wasn't the only one). With that in mind I created the heat-map below to visually represent STATES with the most Final Four appearances to its credit from 1979-2011.
It should come as no surprise that North Carolina owns this map, with Duke, North Carolina, and NC State (combining for 21 trips) but Final Four representation is pretty evenly spread around (with the exception of the ENTIRE north west).
Note: Butler is in Indiana (now you know).
Here's Google's breakdown of the NCAA D1 Teams for this year.
Data provided by CBS Sports