Who.is will tell you the register's name, but that doesn't assure you that it's the owners name since they might be using fake information to register the domain.
The private whois email will land at their legitimate email. Send them a message and see who replies.
In the whois details you'll find the registrar, contact them and tell that you want to buy this website, they should contact with the owner. You should ask the registrar to give the owner's e-mail to conduct the selling process because you want to conduct it by your broker and it must by done privately.
