Menards will have them. Ask for a stud finder.
They have several different stud finders there. They're easy to use, too.
Stud finder
I have a Stanley stud finder with vert/hori levels and laser on it. Highly recommend one with those features.
Or you can take e hammer and tap lightly on the wall along the area that you want to hang it. A hollow sound will be made in between the studs. Then take a drill and drill a small hole on each side of the hard sound to find the stud. The drill will have wood on the drill bit where the stud is located. The bit will have white drywall powder on it in the hollow space. Saves a few bucks and the time it takes going to the store...IJSR!
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