From my experiances putting them in choke points worked well, but just about any spot worked provided you have some type of bait in there and the minnows are present as flathunter stated. Check often, seems water snakes are drawn to these things.
I usually throw a large rock inside of it to keep it on the bottom. Tie some fishing line to it and then to a tree to keep it from floating away. I use white bread and pack it around a smaller rock, this keeps the bread at the bottom ofthe trap and the fish can't eat it from the outside. Everytime I use it I end up with so many minnows for bait that I just pick the right sized ones out and throw the rest back. If you are near Akron let me know and I will tell you a great spot to put it.
I just reread yur post and noticed you are from Cinci probably not worth the trip to Akron to get bait, but if any of you other guys that have not had success are near Akron let me know if you want a good spot, just leave some for me.
Have had one for years, I use cheap dog food dry kind, load it up not a bunch but a cupful, I like to put it in a deep hole, have a creek near the house, put the ends so that they face into the current and it should stay near the bottom, I like to use the camo colored twine, so it's hard to see, I use an old T handle to push flush into the ground, cover the twine up with grass, if somebody see's it they will walk off with it, and several times I have had water snakes get in and chow down on the minners, but they only do it one time, last supper as they gorge themselves to the point where they cannot get out of the end holes, and they got to breath so death in a basket is there finale, great way to get bait and it is very lively.............Doc