Your 2014 regional sites are
Worcester, MA (Northeast)
Bridgeport, CT (East)
Cincinnati (Midwest) - US Bank Arena (where Michigan won the '96 title)
St Paul (West) - Xcel Center
I don't know all of the ins-and-outs of this, but the NCAA freakin loves putting regionals in Worcester, Bridgeport, and St Paul. It seems like they're there almost every year. I'm not sure why Michigan and New York state don't host more since Michigan has 7 D1 teams and New York has 10. However, I should say that these regionals will probably not be empty caverns of emptiness.