Just look for gold caches and artifacts (hunger charms can be sold 50 gold each). Also, you'll find some gold in the giantess and arachne's caves, and you'll get rewards for completing Madame's quests and the Quetzal quest. Yeah, and you can rob Trudy and the cutpurse if you defeat them. Prostituting at the brothel will also earn you some money, but eventually you'll get a red perk and you won't get paid for whoring anymore. And then, there is the bank where you can take up to 200 gold credit, which you do not need to repay as long as you are ok with letting the collector fuck you every few turns