Any good shop will train you, and pay for you to take the various binding cert tests. You could take one of those courses, but shops have diferent tuning machines, and they may or may not have helped at all for the particular shop you will be working at.
Best advice is to pick up a tuning video (websites dont cut it because you cant see anything being done) and read buyers guides until you die. Not just the freeskiers buyers guide because from a tech standpoint, its a horribly put together piece. Read Ski, Skiing, Powder, FS...all of them and get your knowledge of the entire sport down. I am a freeride supervisor at my shop, but when we hire, we look for techs, sales, and rental bitches to know their stuff across the board including outerwear, hard goods, tuning, and technical skiing advice including biomechanics and intruction techniques (hints and tips)
So yea, that was alot longer than I expected to write. Just get your head in the game, dont be afraid to make friends outside the park, and after a season or two, you should be ready to start at most shops. Hope this helped.