It's in the hallway behind Club Cool (where you can sample international coke products). If you are on the "Land Pavillion" side of the building there was a sign outside for the Annual Pass Magnets. You pick up the wrist bands at the same place. Everyone seemed more focused on the magnets--I got my magnet and then asked about the wristbands and they had them and they asked which time I wanted the bands for.
FYI for the magnets, they are scanning MB's so they can keep track of who has already picked up their magnet. Not sure if this was done in the past for AP items. Hopefully that means they don't run out.