You're gonna have a rough idea of tunes you wanna slot into a set, ie. the tune that dude off doa just sent you or the tune you just picked up from the local shop etc.. but I can't think of anyone wanting to jot pitches down.
its too dynamic a thing to plan to that level, fair play if you're doing a mix cd thats gonna be pressed a million times over, it's gotta be spot on, but with experience, any DJ gets the "ear" and can recognise and adjust pitch very, very quickly.
I've seen one person who was playing at a night (his first time playin out) and he was working for weeks planning his set, stopping just short of noting pitches down (he had a predone tracklist in his bag and just worked off that). Which is fuckin ace if you're the first guy up, but the 2 dudes on before him clattered at least 3/4 of his set before he got chance to put stylus to vinyl. Not a good thing!
Even if you do go in there with a rough idea for a set, take half as much records again on top, just to spice it up a bit and allow yourself room to breathe.
Slot in a couple of old gems you know inside out too, so if you're starting to shit it a bit, you can just auto-pilot thru a couple of mixes to regain your confidence