You are doing what you should: the Labor Dept. enforces the labor laws and wage & hour rules, so they are the first step in collecting the compensation due you when you were mischaracterized, as you appear to have been based on what you write. If your state labor board is not being as responsive as they might, try contacting also the U.S. Dept. of Labor; if neither is helpful you can sue (you'll want to retain an employment lawyer for that), but starting with the labor department is a good idea, because you don't have to pay for their help.