Toronto has 2 major airports. Toronto Pearson is the international airport and is the location for almost all the major domestic and international airlines. It's about a 35 minute drive from Toronto Pearson to the University of Toronto, but be aware that downtown Toronto traffic is busy all day and is particularly busy during peak rush hour. Allow at least an hour for travel time from the airport. The Union Pearson Express train is also an good option to get downtown from Pearson.
VIA Rail is offering a 10% discount for PyCon Canada 2016 attendees travelling to Toronto between November 8th to 17th. Use the conference discount code: 13389.
Make sure that you've got a valid passport and don't forget to bring it with you.
Porter Airlines has frequent, reasonably priced flights for trips from several US cities to Toronto, including Boston, Burlington (VT), Chicago, Myrtle Beach, New York, and Washington.