uhhh, I dunno? There're a few upgrades, but none called "Gold" that I know of. Unless it's someone offering to sell you "gold" within the game. They earn gold coins through their characters, and then sell your character the gold coins they earned for REAL money from you.
If that's it, it's a totally NOT OK thing to do according to the rules of WoW. I can ask SKnot who you'd report the spam to, if you'd like. Someone within Blizzard (the company that owns WoW) would love to disable the spammer's WoW account.
"If Americans want to live the American Dream, they should go to Denmark." - Richard Wilkinson