The link below will direct you to an older DFP thread with a link to a "pitch call chart". It's a good starting point to begin the adventure. From there, hours of watching SB/BB, discussion, debate, and hands-on experience are needed to take it to the next levels. IMO, its a wonderful journey with no end or fixed destination! http://www.discussfastpitch.com/softball-discussions/1821-pitch-call-chart.html
There's a dvd called "Calling A Perfect Game," which supposedly concentrates on exactly this part of the game. I've never watched it, but I've wondered if it's any good and thought about getting it. Has anyone seen it? It's by Linda Wells who coached at ASU and coached the Greek olympic softball team and Stacey Farnworth who played at ASU and caught for the Greek team.