Just checked my source, and don't see Milan Dragway listed. Best bet is to do a search between 460.000 and 470.000 if they're using UHF. For VHF, program in all the MURS frequencies. Odds are they are using one of them.
By the way, if there are any short track racing fans, check
here for any specific local race tracks, special races and touring series. If you follow racing in central and northern lower Michigan, you'll probably see my rescue team at a few of the tracks.