I work part-time for a business with only six workers, and I make $5 per hour. The company sells things online for people who don't have the time or know-how to do it themselves, then takes part of the proceeds as a fee. The owner told me he doesn't have to pay minimum wage because it is such a small business. Is this true?
First of all, hats off to you for looking up your rights. As you have no doubt discovered, your boss is paying you less than the federal minimum wage, set out in the Fair Labor Standards Act. (The minimum wage is currently $7.25.) Any company that engages in "interstate commerce" must pay the federal minimum wage, no matter how many or how few employees it has. As a practical matter, this means the vast majority of businesses are subject to the minimum wage -- and, based on your description of what it does, your company is too.
Your state's minimum wage might be even higher, and your local county or city government might also have a more generous minimum wage. Employers have to follow whichever wage law is most generous to employees.
As for what you can do about this situation, your first course of action should be to tell your employer, in a respectful tone, that he is wrong, Wrong, WRONG! In other words, point out that he is legally required to pay you the minimum wage. If those pleas fall on deaf ears, contact your state labor department. If your employer has violated the law, you might be entitled to collect back pay -- the money you would have earned had you been paid the actual minimum wage rather than the imaginary "I only have six workers so I don't have to follow the law" minimum wage.