Here's the web site for Brampton Flying Club
http://www.bramfly.com/
All the schools that I have mentioned can take you all the way to CPL-multi/IFR. If you are coming out in May, I'd suggest you to rent a car and drive out to all the different schools to check them out. If you find the school that you like, don't hesitate to take a "Fam" (familarisation) flight with them. It will take 0.5 hr and it's usually cheaper than the cost of a real flying lesson.
As Squawk said, Oshawa is a nice airport to learn to fly. It is an under-used airport and has a control tower, 2 non-precision approaches, and is not far from the practice area. Brampton is just the opposite. Regarding Durham Flight Centre, I heard their C310 is out of service so you'd better check that out. The City Centre Airport is nice but getting there is a hassle. I hate waiting for the ferry and the extra toll that I have to pay. Oh, forgot to mention about the parking, it is expensive. Markham airport is far from the downtown area but is close to the practice area. The runway is short (2000') and is in pretty rough shape. I guess if you can land a Seminole there, you can land it anywhere. I believe they are the least expensive when compared to the other schools.