[T.G]

Look at the nameplate data on the fans, it should give an operating voltage range, for example 7 - 12VDC, and an amperage, then go find an old wall wart transformer that is within that range, and outputs at least that much amperage. Something from 6-9 volts would work well to keep the fan speed down where it isn't so noisy or blowing like a hurricane.

Cut the connector off the end of the output lead on the wall wart, strip back the wires, connect (solder, crimp, wirenut) the marked wire (one of the two wires will have a ridge or a inked dash running the length of the wire) to the red (+) lead from the fan, and the unmarked wire to the black (-) lead. If you aren't sure which lead is which from the transformer, double check with a meter.

Mount the fan where ever you want, run the cable out under the door seal and plug in.

If you really want to be slick, before you attach the fan leads to the transformer, run the output cord from the wall wart up through the drain hole of the wine fridge, then connect it to the fan leads and re-seal the drain.

You can usually pick up the transformers at thrift stores for a buck or two, assuming you don't already have one lying around with some piece of old electronics that you've been meaning to throw out but haven't.