I haven't seen a gold spammer in zone chat for over a week, maybe two. BUT it's flooded with guilds spamming for more members. I'm not interested...at all.
I'm using X4D for filtering and I've asked for input on creating regular expressions to filter out but there've been no replies to that addon's forum for a couple of weeks now.
or try SpamBayes, you don't build regular expression with it, you train a few messages as ham(legit) and spam(unlegit), and the database of words built in the background is used to weight all messages with the bayesian algo
In your case, you train some guild message as spam and other messages as ham and it will be capable of catching all of them
in the screenshot you can see I have trained a few gold and vampire bite message as spam and it is catching all of them