No such thing for TA and airline agents.

If you're talking about how the pricing elements of fares themselves are calculated then you pretty much won't find it anywhere: it's all commercially sensitive. You can find out what the elements are easily enough, but not how they're generated by the airlines. That said, I'm fairly certain that some airlines just make shite up to see if pax are stupid enough to pay it. BA & QF fuel surcharges, I'm looking at you.