Other than the ones right on my property, I have taken most by driving the more overgrown roads and jumping them. Watch where they land and focus around there. If the road is abandoned and not a county maintained road, it is legal to shoot them there, but not truly ethical unless you are assured of your background.
Some of the bigger ones I got last year were out in the grass off of the sides of the road up Sand Canyon. Shot two right in the first big campground area out in the middle of all that grass.