OP, i know it's poking the nose in a somewhat old thread, but still, as I've started taking part in the discussion after some long break, I'm just trying to take contribute in the areas I know a word or two. Well, how the sellers have collected the email list? is question with quite a few answers. They may have scrapped from forums, etc. And this would be a low-quality list and waste of time and money mostly. I would suggest dealing if someone has managed service of email infrastructure provider, or sender of sizeable email volumes for clients, you may find better leads from them. Let me know if I can be of any help.