The free t-shirt is in a box at the plaza. The maracas are in the Cove. Those are the only two free items. If you are a member, go buy a backstage pass at the Snow Forts and then go to the VIP area behind the stage at the Dock. You will go to a special room where you can buy musical instruments. There is a secret red guitar you can get if you click the dot on the i in the word Music in the catalog.