It depends on whether the anonymous person has an ID number or not. If he or she does you merely need to click on the name of the poster and that will put you at that poster's g2g profile do it again and you'll go to the appropriate personal profile. that should let you send a personal message. However, I see that you don't have an ID, so I'm not positive if you're allowed to send personal messages here before you become a full member or not. But give it a try first and if that doesn't work, come back to this message and we'll try something else.