Reply to the Sender of the Email Reply to the sender of the email, saying that you do not wish to receive such mailings, and that you object to such activities. If the message offers a way to remove yourself from a list, use it. Many addresses that bulk email appears to be sent from are forged, so be aware these messages may bounce. Although this information can be forged, it's usually more useful than the names of intervening sites. Reply to the ISP Flaming seems to serve no purpose, and certainly doesn't reduce the volume.
Spammers expect flames, presumably, and it is just like water off a duck's back.
Send all bulk emailers your business opportunity. You say all this junk e-mail is stopping you getting on with your business. But, these people are trying to do business with you. Here is another name that wants to do business with you. Once one of you starts and performance is experienced, trust develops.