There are tours on Mon-Thu at 2:00PM. They are all on after each faculty welcome, so if you go to your faculty welcome there is a tour that leaves from just outside where you are. If you can't make it for some reason then you can go on another tour (though you may end up being the only non-Engineer there or something). The tour leaders will be trying to tailor each tour to the type of students in the tour, so if there are a lot of Commerce students (for example), then they will talk more about the Commerce related buildings (John Goodsell, Quad, etc).
Here are the locations of all the tours and which faculty welcome they accompany (they are all 2:00PM-4:00PM):
Monday (Arts): Morven Brown Courtyard
Monday (Built Environment): Naked Lady Lawn
Tuesday (Medicine): The Pavilions
Tuesday (Commerce and Economics): The Pavilions
Wednesday (Science): Physics Lawn
Thursday (Law): Roundhouse
Thursday (Engineering): The Pavilions
I'll be taking an Engineering and Medicine tour, so if any of you are going on one of those tours you may have the unfortunate luck of getting me as a tour leader! Pray for mercy.