Well if there would be such a website or service then no one would want to be a client of such fraudulent company, right?
The only way is for you yourself to figure out what the boss might be doing wrong. Is he forging documents or asking you to lie about anything? Maybe compare it to other similar business.
Rednails, I am thinking that you can ask previous employees what it was like working there and from how they answer and what they answer you can usually get a clear picture of what is going on in a work setting. In general, I think you should ask around about it.