I want to apologise for a potentially stupid question, but as a self-taught player I sometimes find myself in situations when I can't find a proper material.
What are the best books/websites that explain theory behind songs, i.e. not only teach which finger to put on which bar or what key to press? I have some knowledge in music theory, but I don't know how much of it I still don't know. So I want to reed some materials explaining different songs and genres to see how musicians actually apply theory to practice and how different aspects make music "distinguishable" (why Spanish music is different from Beatles songs?)