Note: while I try hard not to break links, and so the following will still function, this page is no longer being maintained. See the Craft-by-Craft Contents for the status quo.
… and Resources. There is, of course, overlap between this menu category and the other two.
Crochet Reference has stitch abbreviations and pattern conventions as well as selected resources and technique references.
Sewing Tidbits is a mini-encyclopedia of tips, techniques, and resources.
The penultimate section of Learn Crochet consists of the techniques needed for amigurumi, both crochet and not.