Please ask an SGM from each shift to keep up a live chat log of each main city up on one of their screens. Please have them IP-ban anyone who advertises an RMT site, ban any payments from that account's credit cards, or whatever it takes. Blacklisting is no longer a viable solution--everyone's just removing /shout from their chat log entirely because, in cities, you can't keep up with blacklisting everyone. Hell, in Ul'dah at present, I can't even right-click a name before another RMT shout moves it up. I realize your support team is needed elsewhere, but it can't be up to the playerbase to fill out a ticket with EVERY RMT's name (which is what my most recent ticket instructed me to do)
I didn't find the right solution from the Internet.