Tapestry Crochet Blogs
These blogs focus on the technique of Tapestry Crochet.
Yarn Company Blogs -- Blogs Maintained by Yarn Manufacturers and Distributors
These blogs are all maintained by yarn companies. They feature information about yarns, knitting, crochet, and other crafts that utilize yarn.
Yarn Spinners' Blogs
These blogs are maintained by hand spinners who produce gorgeous handspun yarns for crochet, knitting, or other crafts.
Yarn Store Blogs -- Including Blogs Maintained by Online Yarn Stores
These blogs tend to focus on yarn, not necessarily crochet; you might or might not find information about crochet, knitting or other crafts amid all the yarn posts. I've tried to pick blogs that do at least feature some crochet information, but on any given day, you never know what you'll find when you click.