Where I do my research and find my ideas.
Mexicolore, my beloved. Best source on Aztec/Maya religion, second goes to good ol Wikipedia. It's ran by anthropologists who are obsessed with Mexico. God. I wish I were them!
Wikipedia, of course-but it is worth mentioning that while it isn't a bad source, it's best to scroll straight down to the bottom and read from the sources, as some articles can be a little misunformed. I use Wikipedia to research on Celtic, Chinese, Japanese, and Russian folklore.
More Aztec Maya, can be found via Mexicaheart's Tumblr/Insta. He participates in indigenous spirituality often, on top of being an artist, so you get a window into how "myth" is still important to people to this day.
Here's a handy site for Irish basics called Emerald Isle. The info is short and sweet and gets to the point. They have a Patreon for supporting them as well.
Art that inspires me to keep writing, and has similar themes to what I write. That, or it has similar worldbuilding. Or, I stole worldbuilding beats from it and changed it because it isn't as fleshed out as I'd like.