Uhm since the topic states "Don't get scammed" wouldn't this be more about trades, than fake GM's and phishers?
I mean.. Giving out your info to a 3rd party doesn't mean you've been scammed. Just means you've fallen for an ancient trick, and quite literally, should spend more than 30 minutes online a month.
Fake GS's are nothing. They are annoying, but again, nothing to worry about.
A GS, fake or real, can't do any harm to you, unless you've broken rules, and then they need to report it to a GM.. So nothing much to be worried about.
Persons history is quite nice, but i wouldn't like asking in a global chat if someone is legit or not, and if i went through a party or guild chat, chances are people don't know the person.
Also, theres the chance that the player only scams one person per character, and since no one other than the GM's can look up account names based on characters, well yeah.
If i were to make a don't get scammed guide, i would focus on stuff like "Double check your trade window before accepting" and "Be aware when a good deal seems TOO good".
Other than that, there's the use of what has now become "uncommon sense", since common sense is not all that common anymore.
My 2 cents of feedback