While there, you may want to listen to the behind-the-scenes action on several sets of frequencies.
New @ 8/9/98 - There have been recent changes to the frequencies used by the Bethlehem trunked radio system; rather than track them here, I'll refer you to Nick Lechman's excellent page at http://members.tripod.com/~Scanning_Bethlehem/Lots of activity on the trunked system after 5 PM as festival-goers come to town. During the day you may hear municipal workers getting things ready. Heavy Bethlehem police and fire presences at the festival.
151.625 (itinerate business)
Most operations on 151.685 with calls to base which will relay to mobiles. Also heard some food vendors and transporation coordinators on 151.625.
probably others as both cable and radio stations cover the festival live.