If you want to go the HAM route, declare an emergency, transmit "MAYDAY, MAYDAY, MAYDAY" on IDAHO STATE COM (155.550) If you think Idaho SAR is in the area and looking for you - transmit on 155.160.
The only problem with this is that 155.550MHz is not a HAM frequency. 2 meter HAM radio is 144 to 148.
I live in Boise and do most of my hiking in central Idaho (which is pretty much the black hole of cellular coverage) and have not been able to find much information on what radios or frequencies are in use. This is good information. I carry a 2 meter handheld with me and tell my wife if I come up missing I'll trasmit on 146.520 if I'm able and hope someone on the SAR is a ham. Any more information on this would be appreciated.
My wife and I decided that since I do a lot of solo hiking getting a PLB would be a good insurance policy and would give her a little more peace of mind while I'm out. It seems like a lot of money but it'll seem pretty cheap if I ever need to activate it.