Outdoor Faucet problem

I have an outdoor faucet that seems to be leaking on the inside of the wall. When the faucet is on, water will drip down from the siding and also come out of a hole in the brick at the end of the house. I do not have a basement, and I can not find any type of access panel. The faucet is on the outside wall directly behind my kitchen sink. Anybody have any suggestions, or do I have to call a plumber. If I should call someone, what is a good way to find a good one for this problem?

You have a frostproof hose bib there, if where it screws into the wall fitting is secure then you should be able to unscrew it and install a new one, turn off the water first.