Fibre Fusion sells a variety of books relevant to the beginner through to the advanced feltmaker.
Art in Felt & Stitch - Moy Mackay
Fabulous Felted Scarves
Felt to Stitch, Creative Felting for Textile Artists by Sheila Smith
Little Needle-Felt Animals
Needle Felties: Twenty to Make
The Ashford Book of Needle Felting
The Complete Photo Guide To Felting