I live in Niagara Falls (during the summer) and there are some great locations here - but probably not the ones you'll read about in guidebooks. My favourite place in the Niagara region is the Niagara Glen, which is an area about 10km downriver from the Falls, near the Whirlpool. There is a great set of trails (across from the golf course) and plenty of photo ops. Next week I plan on making a run down there to catch the morning light with my new camera.
Niagara-on-the-lake, a 30km drive downriver from the Falls, is quite pastoral, and has some nice photo opportunities.
In Toronto itself, the University of Toronto campus is beautiful, particularly University College, (my college

) , Convocation Hall, and Trinity College.