I just got word that Mary Youngblood's concert tomorrow (Oct 3, 2009) at Moaning Caverns has been cancelled because Mary is ill. I don't have any specifics on Mary's condition, but add her to your prayers for a speedy recovery.
If you have tickets, contact Moaning Caverns for information on what to do about your ticket. I am not sure that it will be rescheduled, but if I hear anything, I will post the information. Feel free to add a comment if you know more.