If I was owed wages by a company I quit how could I force them to pay me?

You would sue the company to force them to pay you. If you did the work, you are legally entitled to be paid for it, even if you then quit. If you were not exempt from overtime (and note: hourly employees are NEVER exempt from overtime), you should have been paid at time-and-half for all hours over 40 worked during that work week (i.e. for 18.5 hours). The way to get your money is to sue. You may wish to consider suing in small claims court, where you could act as your own attorney and where the filing fees are small. (Also, small claims cases tend to move faster than cases in other courts.)