how can I block what I consider to be scam e-mails.

getting many different e-mails from different e-mail addresses stating they have money for me at western union since the scams are from different e-mail addresses and I generally only get 1 e-mail each time the e-mail addresses are not repeating but I keep getting these types of e-mails how can I get rid of these types of e-mails. I find them very annoying. I have a pop-up blocker but they are coming on to my junk mail address.