Hello, sweetling! You can earn currency by hunting for medals and achieving quests given to the NPC's in the Missionpoint map. The bronze medals are the cheapest, then there are silver medals, gold medals, diamond medals and ruby medals, respectively, from cheapest to the most expensive of medals. As for prey that won't drop items, I suggest searching through the Wiki on the forum, you can find an item that you're looking for and said item will have a list of prey that will drop that item. However, sometimes items don't drop right away, so it's best to just keep hunting until you finally get the item you want. You may use the NPC's in the Bazaar map and there is a large variety of things to choose from. Just get the medals you need in order to purchase the item, shard or pet that you want and you'll be able to buy it. I hope this helps! Good luck and have fun!