stalker / stocker [ˈstɒkɜr]
stalker – n. – 1. one who prowls about for purposes of theft, or follows someone for illicit purposes; 2. a kind of net used by poachers; 3. a poacher
stocker – n. – 1. a workman employed in felling or grubbing up trees; 2. a craftsman who makes or fits guns; 3. someone who ensures that shelves have sufficient merchandise