A. Call the carpenters' union and take whoever they send over.
B. Ask some carpenters you trust if they know any decent carpenters who are looking for work, and when they show up at the job site sober with appropriate tools, you put them to work.
It's a slightly different process than programming.
However every so often we do have to advertise for a position, and then the process of weeding through the applications probably isn't so different from what everyone else has to do.
At this point in my career I can say that it's quite easy to spot a skilled carpenter if I spend a few hours with them. I imagine an experienced programmer could do the same. The problem is getting to that point.
Bingo, this whole topic in a nutshell.