National Guard Freqs are found at the botton of the Lancaster County page on the DB:
Lancaster County, Nebraska (NE) Scanner Frequencies and Radio Frequency Reference
Prior to 2004, they used 149.475 Analog. In about 2005, they switched to P25 digital. Last time I listened they used 150.325 as thier primary channel and it was encrypted almost all of the time. Very rarely, I did hear P25 non-encrypted comms. Thier comms are all simplex, so unless you are close, you won't hear the mobiles.
Punch in the freqs, and let us know what you hear.
Cheers,
Joe