I did an eBird search for your area. Here is a link to it http://ebird.org/ebi...9&continue.y=11
From that chart you can click on the map link next to each species name and see the actual locations of the reports. The ones in red are recent reports and the ones in blue are older ones.
I think your best bet would be Mohawk Park north of Tulsa. There are many reports, some recent, for Great-horned and Barred from there and I would imagine Screech Owls are there also.
Barred Owls like to roost in pine trees. They also tend to like wet bottom land type habitat along creeks and rivers. They are also the most vocal so sometimes you can use that to narrow down your search.
Great-horned Owls tend to hunt like hawks along edges of fields. Sometimes you can see them silhouetted against the sky at sunset perched in trees. They should be on nest right now so the reports of them at Mohawk are probably a nesting pair. Look for their nest in old hawk nests, or the crotch of a big tree.
Screech Owls are common but they roost in cavities so they can be very difficult to find. They are also tiny and really well camouflaged. I got mine by being taken to a roost box someone placed in their back yard. Your best bet is for one of these is going to where one has already been found.
Long-eared Owls tend to stay hidden deep in pine trees during the day. they can be one of the hardest Owls to find and get good looks at. You pretty much have to stalk through a stand of Cedars/Pines and study each tree. You have to be careful though because they will flush easily.They use the same roost, sometimes years in a row, so a large amount of white wash(poop) can accumulate on the tree which can be an aide in IDing roost trees.
Short-eared Owls CAN BE the easiest Owl to observe since they will come out in daylight more than other owls, like open spaces, and roost on the ground. They tend to be rather local though, congregating at certain fields when they winter so if you are not looking in the right field they can easily be missed. Areas that have large numbers of Harriers are good places to look for SEO because they both like the same habitat.
Barn Owls are declining in most areas and many field guides range maps are not the best, there may be a few around but may be difficult to find.
I would say overall the best way to find them is to monitor eBird for sightings and get involved in your local birding community by joining your local birding club/Audubon, going on field trips, reporting your sightings online for others, etc. Owls are birds that some birders do not report because of the sensitivity of how they must be viewed, they do not want them harassed on their roost. So getting to know local birders you get to be privy to information that they do not want getting out to the masses. It never hurts to make new birding friends anyway.