#1- GMs usually have the word "the" in their name. I can use that to my advantage.
An example, Brenlo the Bixiebopper. In almost all of these cases, the name in the struct will be Brenlo, and the surname will be the Bixiebopper. However, GMs can break the rules in this regard. A more important problem though... if they don't appear in superwho, what would you look at in order to search for "the"?
#2- GMs like to be level 65 on 99% of the servers.
True enough. They can change their level without notice, but they are almost always level 65.
#3- Even if they aren't detectable the whole time, someone said that they are when they first zone in.
I have reservations about this. I believe this only affects those with the avatar level Guide, who has the worst of the stealth available. The best I can see available, if indeed a GM appears in superwho briefly when they zone in (something I am actually certain is false, now that I think about some of what I know), is to continuously monitor the list looking for them to appear. Because they come off the list quickly, you would either have to consume an overwhelming amount of CPU resources polling for this, or you would have to decode the incoming packet stream.
Good luck with it and whatever you learn in your pursuit. If you make progress I am sure many would be interested. Then again, if you do make progress, I would suggest only telling a select few that you trust not to leak it, because its likely Sony would examine how and change things on their end.