Jeff, it's easier to see the nest in the Fall when the leaves are off the trees. I used to be amazed at the number of hornets nests I would see when I was out in the duck blind in the backwaters of the Mississippi River. Almost all the hornet's nests I've seen have been hanging from tree limbs. I've seen them as low as about 6 feet off the ground and as high as about 25 feet up in a tree. But once I had a huge hornets nest under my deck stairs hanging under one of the steps about 6 feet off the ground. One year, as I sat in my duck blind, I counted 8 huge hornets nest off in front of me in the woods. Yep, Fall will be the best time for finding that nest.
One Fall, when I lived in Stewartville, Minnesota, I looked out the kitchen window to see a huge hornet nest in the maple tree. It had been hidden by the leaves. I waited until January when the hornets were all sleeping......

.......I took the nest down and tore the paper shell away from it. Inside are several flat disk stacked on each other with a spindle between them. Kind of like a high rise apartment. Each disk has a couiple of rows of holes around the rim where the eggs are layed. It's quite interesting.