I need info!

Who would be the best person to talk to about starting a union? I work for a private ambulance service in wisconsin. One of our local hospitals just voted and are starting one and I want to do the same. We are basically treated like we're disposable and not people. We haven't had raises in three years and when we did, it was way, way less than cost of living increases/ inflation (one coworker stated her 2.67% was $0.92).