To see a member's profile when you know their user name or part of it -

Login first (click 'Register" if you haven't joined)
Click on "User List" on the horizontal menu bar on the upper part of most Shop Talk pages.
* If they are a fairly active member, click on the first letter of their name in the alphabet links in the box.
Scroll down that list to find the member and click on their name to see their Profile.
* If they are not on that first page, put part or all of their user name in the member search box and click to search. That will search only in that alphabetical group and display a list with a narrower result of links to Profiles. Note the date of when they were last online in the forum. Click on their name to see their Profile.

In their Profile, they may have listed an email or phone, or not. They may have listed a PM (internal Shop Talk message) or not. Usually it is both or one or the other.
Send them a message on a PM or email. PM messages may not work well if the member has not been online in the forum for a while.

If their email bounces or you don't get a response, try sending a PM message.