blocking an email address

I'm tired of trying to figure it out. How do you block an email address in Mail? Everything I try doesn't work. I can mark it as junk but it keeps coming back. I Guess the next step is to tell the person to leave me alone.

I don't use Mail but I found this howto. Does that work?

Thanks for the help. I'll give it a try and see what happens.

If not, feel free to post their email address, or send it to me... I'll spam the crap out of them.