I'll throw in my $.02 here.
We did the tour in October of last year as well.
Tour started in Epcot, we went behind the scenes at the American Pavilion and at Body Wars. Body Wars was cool to see from the outside with the lights on. That ride really moves alot more than people think it does.
Then over to MGM where we had lunch at Mama Rosa's. Like other said, this was a good meal. I know my wife has told me that we need to add this one to our restaurant list next time we visit. Then on to the workshops. Wood, metal, robotics, costumes, uniforms. We got to see how Disney builds all this stuff, and to walk the halls where all the creative staff works. The robotics stuff was very cool. We also toured the Christmas warehouse were they were gearing up to decorate all the parks and the two ships.
Then over to MK. Did the Utilidor, watched the 3:00 parade, a walk up main street, then over to where the parade ends and we got to see the place were they reherse for the parades and all the floats.
Then we were taken back to Epcot, and it ended.
It's a really long day (7 hours), so ready your feet for some pavment pounding. They do bus you around, but you're still on your feet most of the day. Everyone should do this one at least once, but once was enough for us, we wont do do it again. Thes cost was $200, but I could use my DC to get a discount.
As for booking, we just booked through Disney, the same as the room. Actually, that's wrong, we stayed at AKL concierge, and they booked it for us. But the year before, we did our own bookings through Disney, and we just booked through them.