You might consider setting up a video camera and pointing it at the location where you keep the things that have disappeared. If your wife still keeps a wand in her dresser drawer or wherever, keep the camera pointed on that overnight (with a wand in there), and record all night long. If the wand is missing in the morning, check out the tape to see if you notice anything. If it's still there, just repeat the videotaping for a while to see if you pick up anything interesting. Or the same thing for the wallet, etc.
Just a thought, anyway.