Speak with Gryphon Master Talonaxe inside the Aerie Peak Aviary.
So you're a glorified errand $g boy:girl; for some old Explorers' League geezer, eh?
Well you listen to me, [class]. I don't know who your old buddy was flying around with down in Azeroth. Do I look like Gryphon Master Talonaxe to you? Do I?
If you're so interested in the flight assignments why don't you ask the gryphon master? If I catch you idling around here for much longer, I'm going to put you to some real work.
Now get a move on.