Answer: Although they can be a nuisance with their tunnels, moles do not harm plants so be sure you need to get rid of them before you try trapping. Your local county extension should be able to tell you where to find them locally. They should also have suggestions as to how to control the moles and how best to place the traps.
I would expect hardware or farm supply stores to carry them. Your local pest control company might be able to tell you specifically.
Otherwise you could try mail order, in a brief google search I found that Ace Hardware offers them for example. You may need to cut and paste the complete url to make it work correctly.
I hope this helps.
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