Online website contact information Scraper

I'm looking for a service or a tool that can scrape emails based on certain criteria. I want it to scrape email addresses of the users of membership sites.

I found a tool but I forgot to bookmark it now don't even remember what it's call. Does anybody have any idea? I was looking to outsource this to people, but I don't know anybody trustworthy enough with my login info. So an intelligent software that can log itself into a membership site and collects information would be helpful.