"One must distinguish regulation (which often is specific to a certain area of business) from law (which is more general). For example, there are laws against fraud, and long before governments began to regulate the US economy, people brought alleged fraud cases to court, as well as other tort action that existed under a common law system."

"Private enterprise works on a voluntary basis, a business owner cannot coerce someone to do business with him. Things like loss of reputation, shoddy products, poor service and the like serve as real boundaries for business owners, who in a free market survive only by offering goods that people are willing to purchase.

There are numerous private (read that, voluntary) organizations that police businesses, settle disputes, independently test products, and provide needed information for consumers and producers alike. Yes, these organizations do have a regulating effect upon the behavior of individuals who participate in private production and exchange."

Edit: removed the conclusions, the rest - in my opinion - is relevant to the comment above.