Gorilla Resources Blog is THE place where you can find a really well selected compilation of websites dedicated to animation and it’s so great that it is divided by every step you normally do when making an animation, from scratch and thumbnails to planning, blocking and polish. Also including some acting and body mechanics articles and how to make your characters stand out on screen. It has articles form all the most talented and important animators in the world.
This is definitely the most transcendental “must have in bookmarks pages” I have found across my life as an animator and I’m glad that you can know it and learn from it too.
It has recently changed its name to Gorilla Resources Page, because when I first knew it, it was called ARC. Just as a little hint.