Thank you.
It really depends on the owl type.
Snowy owls are one of the easy owls to find since they like open fields that mimic the arctic tundra that they are used to. Because of this they'll often be found on top of poles or in fields.
Other owls such as Screech owls will take over holes created by woodpeckers. They also primarily hunt at night and rest during the day. To find these type you have to look in holes that are about diner plate sized in trees. Sunny days are better since they like to warm themselves and will be seen at the entrance to the hole.
Owls such as Saw whet owls are also nocturnal but during the day they like to hide near the trunk of a spruce tree near the 6-10' level.
The best advice I can give you is to learn the habitat that they hunt and roost in. Also learn some of the signs such as pellets at the base of trees/poles or excellent on the trunks of trees. These are great indicators that an owl frequents a location.
You may also wish to befriend other wildlife photographers in your area. Myself and Jr. regularly meet up with other photographers to go out and shoot. We all learn from each other and the more eye's and the multiple experience levels can make it easier to find/learn to find your prey.
One last thing to keep in mind is the stewardship aspect of photographing wildlife. You want to learn what is a comfortable distance from the subject. Some species can be harmed just by getting too close and stressing them. Add to that some may be endangered. Keep this in ind when you're excited and want to get the shot. We'll all make mistakes in with this part (me included) but we should try to learn from it.
I'm going out of town tonight for a bit but I'm back on the 10th. Bump me then and I'll look into the specific owls and see if I can find any signs that may help locate them.
Also have a look here for your area for general locations of sightings.
https://ebird.org/species/eueowl1
Good luck.