Old barns, is one way. When your out driving around and you see a bunch of birds on a wire. Look nearby there should be there home. Alot of people will let you remove the birds for free. Just ask. If you dont see them daily then drive around and look for them . Get permission and go. Night time with a head lamp. fishing net. dusk mask. gunny sack.
I havnt done it in a few years but 20 30 birds was our average. Two people helps.
or you could go down town ans sit on a park bench with some popcorn
