I’m sure you’re probably aware of Derrick Jensen? His book Dreams is a great starting point for thinking about animism and how to tap into the ideas and history. I’ve also found Dancing on our Turtle’s Back by Leanne Simpson amazing as well - although perhaps more political than others.
Great article about throwing away some of the agro/pagan spirituality and a critique of Bronze Age/Iron Age gods. Esp important for European primitivist types who often lean toward Celtic/Viking mythology as a counterpoint to Christianity. Europeans should instead be looking at our own paleolithic cultures: Lascoux, Cheddar, Paviland and the exisiting Saami peoples for inspiration.