Don Baccus , Jul 10, 1997; 09:03 a.m.
I'll put this in good new/bad news form for grins.
The good news is that most species of owls are quite common in suitable habitat, as you've mentioned.
The bad news is that, with the exception of barn owls, they're very effectively camoflauged. That's what all that grey, barred plumage stuff is about. They look like tree bark. So does tree bark. Telling the two apart is tricky and time consuming, so even when you know owls are around, you might walk right past them many times before finding them.
The good news is that they're mostly very territorial during the nesting season, and are generally vocal and this makes them somewhat easy to find.
The bad news is that most are vocal at night...owl biologists become nocturnal during survey season. With the exception of those studying diurnal or crepuscular (i.e. day or sunrise/sunset active) species like short-eared owls.
However, more good news is that many species are sedentary, i.e. don't migrate, and occupy the same territory year round. Once you locate a great-horned owl pair, you are likely to find a pair in the same area for the rest of your life.
Even more good news is that many owl species may be easily approached in the day, once you find them. If they flush when you're some distance away, find other owls - individuals vary a lot. The great horned owls you see on my page are used to people and let you walk right up to them. Many individual owls just tune out during the day, when they're roosting. They may turn a lazy eye on you then sit so still that you don't really get any photo ops unless you shout at them to get their attention.
I strongly suggest budding owl photographers to start with great-horneds. They're common, often somewhat acclimated to people, big so you can shoot them with more modest gear (some on my web page were shot at 200mm), and occupy the same territory for life in many cases. A more realistic starter lens is 400/5.6.
I also suggest you get in contact with your local Audubon or birder's group and ask them about finding great-horned owls. Sometimes these folks can be pretty snooty and uncooperative, but many are eager to help beginners learn the ropes, so to speak. Many Audubon chapters lead field trips, often including owling trips at night during early spring. Going out on such a trip will teach you about specific areas near you that are known to have owl territories, and also will teach you about the use of tapes to find them. Most leaders will be eager to talk to you about the pros/cons of using tapes and some common sense rules of thumb to minimize disturbance. Owl species are pretty resiliant to disturbance, as a group, though. Species you've read about which are in decline, i.e. spotted owl, are declining due to habitat loss. As individuals, they're so resiliant and get used to people so readily that biologists often name them and they'll fly right to a branch when squeaked at, even though the bios then routinely catch and weigh them.
Despite the fact that many species quite quickly get used to the presence of people, keep in mind that many individuals aren't. And keep in mind that great-horneds, in particular, may have a very nasty disposition when young or eggs are involved. This is a bird that can blind you. I've had adults drive me off before I've even known there's a nest around, I've had adults fly away and let me check their nest out, I've had adults just sit there while I practically pet their babies. Individuals are predictable once you make their aquaintance, but until you do, they're unpredictable...