This crochet amigurumi toy bear is a really cool project. You can use any yarn, I would recommend to take any DK weight yarn.
I used 2 yarns held together: DK weight and Lace weight.

Finished measurements: about 6” (15cm) tall

Materials needed:
Yarn in main color
Small amount of Fingering weight yarn in Black
Crochet hook (a little bit smaller then recommended on the yarn label)
Toy stuffing
Safety eyes

Notions:
scissors
tapestry needle
1 marker