Prices vary. Guys specializing in automotive powder-coating will cost more than those who work more for industrial applications. It's basically the same stuff, but the automotive guys may (but not always) do a bit of a better job as they know it's more for looks than for protection (though both are important, of course).
I'm in OR, not OH, but I was quoted $190 for my frame and that included sand-blasting it and cleaning it up prior to application.