You should pre-book. You can try to get in the day of, but don't hold your breath. I went on this tour on sept 29th... and all I can say is wow. I can't believe I paid 75 bucks to go on this. The woman that did the tour was perhaps the most annoying disney employee I've ever met, and proceeded to call us all by the most 'colorful' names I've heard. This is the south, so I go in knowing there's going to be sweeties and honeys, but at the point you call a 50 year old man "Sweet baby child." It's time to realize not everyone is from the south and that can be insulting. For a company that won't allow anyone to point, maybe they might touch on this as well. Worse, the entire thing was done in a question and answer format. If they cut this format out the entire tour could be done in 2 hours. So if you like standing in the sun while people guess at the reason why they used wood for bridges, go for it. (The answer is "Sensory tickles" by the way... said in a tone that was almost obscene.) Oh and at least half the time we were pointed to lightning rods. Seriously? Nothing more interesting in disney than lightning rods? This is the *absolute* first bad thing I've ever said about disney, but this tour was horrendous. I stayed through lunch, and then made some excuse to leave. It's a pity the rest of it was so horrible, I kinda wanted to see the utilidors.