When I wanted to reach someone inside an organization, I sometimes knew their name but not their email address. My original article described a trick using Rapportive in Gmail: try different address patterns and see whether a profile appeared. It was a technical shortcut of its time, not a reliable current method.
Find the right route
Start with the organization's website. Is there a team page, general address or contact form for your subject? A personal introduction through someone you know may be more suitable than guessing an unknown address. Sometimes writing to the general inbox is the best way to ask for the appropriate colleague.
If a business address is public, explain in one short message why you contacted that person. Show its relevance to their work and ask to be redirected if you reached the wrong person. Do not send identical messages to many guessed versions of the same name.
Respect the recipient
My original warning against spam remains essential. The Dutch ACM explains the rules for promotional electronic messages. Finding an address is not automatic permission to market to it. For a personal proposal, a clear relevant question helps more than a clever browser extension. The quality of the contact begins before you press Send.