AnyMailFinder.com - Find anyone's email address
Hunter - Find all the email addresses related to a domain
AeroLeads - AeroLeads is a lead generation software which finds prospects with email and phone number.
Norbert - Norbert is an online tool that helps you to find anyone’s corporate email address.
EmailMatcher - Find anyone's email address in a matter of seconds, for free
Paxtac - A free extension to find email with a full name and domain.