There could be one in Lexington but I know there is a hot rod nationals in Louisville. Never been but plan on going this year.
As far as springfield goes, it is real good for muscle car parts but kind of hard to find some hot rod parts. This year was a bit of an exception more than usual.
Another good show to go to is the cruise in every friday night at the milford Kroger. All kinds of cars from early rods to lotus'. A lot of information can be obtained there.