In Texas, osage grows mainly in central and east TX. Houston has lots of it.
If you don't know any landowners, good luck with getting permission to cut trees. Landowners in Texas get so many requests from strangers wanting to access their land it's ridiculous: real estate investors, deer hunters, artifact seekers, rock hounds, photographers, hikers, bikers, ATV riders, and on and on and on...
Your best bet is to wait until you find osage in a trash heap somewhere. Construction sites are good places, for example.