Are there any high grounds or scenic lookouts or peaks from which foliage can be viewed?
Absolutely! Conservation areas often have them. Here's a picture I took in 2010 from a lookout at the Fleetwood Creek conservation area in Kawartha Lakes:
There are plenty of others in the area. Are you looking to go north or south of Peterborough? Would you like to get a lake involved as well?
The leaves are good right now in this area by the way. I got a gorgeous dose of leaf-peeping just popping out to pick up my veggies from the farm - 5 miles each way along country roads and lots of golds, yellows, and reds on either side of the road and occasionally over it.