happened to me too
took me 3 weeks to catch that rogue bastard
you need to act quick esp w/ the cold
go get a trap:
either buy it
http://www.ebay.com/itm/Havahart-32-...item4cfc233337
or go rent it at a feed store or pet store
lay the trap w/ the stinkiest fish you can get (mackerel worked for me)
caught a possom the first night, a 2nd possom the 2nd night, and my cat the 3rd morning
good luck buddy. hope you get your cat back.