You find them through word of mouth, someone tells you to go in and fill out an application. They'll call you in one or two days and set up an interview time.
When you go for the interview, they will sit you on a folding chair in the tiny office with the owners and the systems admin, and all three will try to ask you questions at one time. There is a lot of talking over each other and you.
If they like you or whatever you told them, you'll be called later that day or the next to be given an orientation.