If the option to send them a private message isn't available on their profile page, then they haven't opened it up for you. Generally, you have to post an initial message before the PM option opens up for you. Then they might have to request a PM from you before you're able to directly PM them.
As was mentioned unless an Official Employee has specifically asked you to send them a private message it is against the Forum Guidelines and the Acceptable Use Policy. You can read about our Private Message policy here.
TomWDTV, Hi! As per the forums guidelines, you aren't able to send a private message until a public post is made. Since you have done that now, you should be able to do so. We also ask that you wait for us to request the private message as well. I do see you have sent me one, so I'll follow up with you there.