Help Find Trisha Patterson

My cousin's 12 year old daughter Trisha Patterson is missing in the Blue Mountains outside of Dayton, WA.  My uncle Jim has a cabin over there, but it is pretty rough terrain and no cell reception.  They believe she has been missing since at least 5 pm tonight, as i think they were all supposed to meet back at the cabin for dinner by then.  No new news as of 9pm.  The Sheriff's office has been notified, however, there protocol requires 24 hours prior to jumping in.  If anyone has any ideas as to contacts, or people who may be willing to help, hikers and trackers in the area - i am sure the help would be greatly appreciated.  My dad along with some of my younger cousins that hunt and are familiar  with the area have headed up tonight to see if they can be of assistance.