Please help, programming frequencies

I got this Radio Shack Pro-164 Scanning Receiver. It worked fine in my previous city, now that I moved away, I would like to program in the frequencies in my local area as well. I found this easier to read manual here: Easier to Read Pro-164/163 PSR300/C/400/C Scanner Manual . I'll read the whole manual if i have to, but is there just an easy way to get it to scan all the frequencies and program in the ones it picks up? If not, could you explain how I can program in my local frequencies? I found a site that shows what they are. Eureka Springs Scanner Frequencies (Carroll County AR) . I looked in the regional section and found a post that helps a little. http://ift.tt/1fMGVFH . I don't understand what trunking is, what fleet# or sub-fleet# are, or if I even need them. Thank you in advance.