Being connected to the Internet allows me to check the FCC database for info on new-found frequencies, etc.
I will also refer frequently to .PDF documents (and others) either online, or stored on my computer. An example: During the recent manhunt for a bank robber in NJ, a file was useful in determining which talkgroups belonged to which troop (there are 3 main troops, each broadcasting through multiple sites).
Recently, I have been using Google Earth to plot my home and each system that I monitor, with its respective sites. I have determined the bearing to each site (using a protractor on screen -- a little crude, I admit) and included the bearing in the site description.
I'm doing this as I plan to have a directional (rotor) antenna someday.
AM