The Animator’s Survival Kit by Richard Williams is an essential book to own whether you’re a beginner or an expert.
Jonathan Abenhaim has an amazing YouTube channel that covers a load of tips, tricks and tutorials on animation. He posts regularly so make sure to subscribe!
Sakugabooru is a huge animation archive used by fans and animators alike to upload and view animation clips from anime movies and shows.
Orca Jobs List is an amazing website for finding jobs in game development and can be filtered to only display specific roles (like animation!)
Cartrdge is a portfolio community for creatives working in video games and is great for creating a page and uploading animations in multiple formats such as Vimeo, Youtube, Gif.. etc
Krita is a free app for digital painting but also supports 2D animation. It is made by artists that want to see affordable art tools for everyone.
Craft is a site that gathers high-quality material from films, graphic novels and other visual media and lets you explore how other professionals crafted it. Giving you access to source files from animators and artists. Free Trial is available.
Live2D has a bunch of software that allows 2D artists to create animations from their artwork. Available in both FREE and PRO versions.
SloMo Ref is a free collection of slow motion animal reference videos on Youtube