I tend to read non-fiction: history, archaeology, folklore, Gaelic polytheism, and witchcraft. I listen to fiction: Scandi-Nordic crime, magical realism, and Scottish authors.
I have tried reading various translations of The Mabinogion, by far this is the easiest translation to read. It helps that the hardcover has two bookmarks, so you can read the notes easily as you go.As an introduction to these myths, this is a great place to start.