The shop called Hot Gossip has a ragged shirt for 30 gold, that's the cheapest item here. All the stores have their cheapest items on their first pages too, so have a quick look to see if you can't afford something you like. And welcome to Mene! :)

Hm, apart from the Exchange.. unless you can sell art or something like that, I can't think of anything. But you can earn up to 500 gold a day from the games, and you earn more gold the longer your posts are. So getting into in-depth discussions, role-playing or posting your stories (if you write) in the literature forum will usually earn you the maximum amount per post. Or you can post a lot of smaller replies in places like the General Discussion where there are threads about all sorts of topics, or in the Menewsha Nation, where you can chat about anything you like. Gold builds up surprisingly fast, even if it seems a little difficult at first. :)