Tim Hortons review: non-payment by employer/restaurant owner

I worked at the Tim Horton's Restaurant here in Southeast Michigan (USA). I am owed two (2) checks, which the franchise restaurant here & the head office in Canada are constantly playing the runaround. They refused to deposit my checks directly to my bank account, then claimed that they sent the checks to my home. I never received them. They owe me over $500. I've tried to file complaints to headquarters but to no avail. Now I cannot get any answers. I need to know who can I complain to, or what I can file, and who do I file against? Any help would be appreciated. I am currently five (5) months pregnant and money is much needed... Thank you!