I got one of those several years ago....it took me three days of reading just to get the local channels. Still don't know about the trunked.
You are missing all of the good stuff if you are not listening to the trunked channels. +1000 on the radioreference and the programming cable and software, it is a must, especially for the Radio Shack version I have. I think the programming manual was written in a different language and transcribed about 3 times!