Animator Airtable is a great place for finding animation resources that utilizes airtable’s spreadsheet features like filtering, grouping, sorting.. etc. Created by Maria Robertson.
Animator Airtable
Animation Methods
Animation Methods is a website hosted by animator David Rodriquez and has links to hundreds of rigs, tools and tutorials.
Thinking Animation
Thinking Animation has a great section on the pros and cons of different rigs. As well as a bunch of other resources and tips across the site.
Animator's Resource Kit 