Interview are in Terminal 2 (Also known as the East Terminal, or the Southwest Terminal). The instructions refer to Door 16, but that's a portion of the airport many folks might never have visited. If you don't know where Door 16 is, go in Door 15, at the northwest corner of the baggage claim level of Terminal 2.

As soon as you enter Door 15, look all the way to your left; you will see an open entry to a hallway marked "International Arrivals", and you will also see some Global Entry signage. Go in that hallway, and keep bearing left and looking for Global Entry signage. You'll walk a total of perhaps 300 or 400 feet, and you will end up in a triangular room where you will see seating for a dozen or so visitors, and the inside of Door 16. Most of the interior doors that lead out of that area are keypad locked. Wait there. There's no receptionist, but every 10 or 15 minutes a CBP agent will stick his head out and see who's there and what appointment time they have. There are restrooms adjacent to the waiting area.

The CBP agent I spoke with was very professional, and the whole visit was painless. I think I was in and out in less than 15 minutes, although I didn't have anything that might require extra attention, like criminal history or travel to sketchy destinations.

Also, I was told that they sometimes are able to accommodate walk-ins on Wednesdays, Fridays, and Saturdays, if they arrive shortly before noon.