I don't think going to the police is a good idea. Soliciting his services for the business visa is possibly illegal too, since only companies can issue a business visa. Lesson is to never release any money in Qatar or elsewhere, until the service has been effected in full. And just curious, how much did he charge you for the visa? Just so you know, a company pays 200 rials, that's it, so anything over and above is his profit. Try calling from some other number. Unless he answers your call, I'm afraid your money might be gone.