I'd like to acquire more, but I don't know exactly what to do to get them. I have gotten some for finds in various states, and a few Hidden Creatures ones that I didn't even know were going to happen. I know there may be one for Leap Day on 2/29 just from surfing the forums here.
Is there a list for these things? A calendar that will describe what dates souvenirs are given out? Any help would be appreciated!