One thing we did the last time we stayed in Niagara Falls, is we bought a pass that got us into several of the attractions (Journey behind the Falls, Maid of the Mist, the Gorge boardwalk and I think a couple other things) as well as unlimited use of the people mover bus system. A lot of the attractions are spread over quite a distance along the river, so the people mover is definitely the way to go. Parking isn't cheap and you'd be moving from one lot to the next. The pass is sold at each attraction, and costs around $40/person.