How do I know if I need a scanner with "trunking" capabilities to pick up local police stuff? - trunking police scanners

Im not sure what you are looking for.
This link has all the frequencies in my area

http://www.radioreference.com/apps/db/?ctid=321

I do not know if it is possible to derive the numbers and letters, if trunking scanner regular pick you up.

Help please! Thank you!