Here is a trick that might work. Purchase a mouse and hold him in a container with some sort of bedding in it. Keep feeding the herps as usual but always make sure that you rub the bedding from the mouse cage on your herp before you offer it as food. Eventually your snake will associate the smell with eating and it will make the switch that much easier. I imagine that store bought lizards are little costly, and wild caught you just don't know what kind of health the lizards are in (very resourceful). I do the wild caught thing with frogs in the summer and fall here in Colorado but I wait a couple of weeks and always feed the best eaters. I will have to state this is not the best way to feed but it works for me.