My favorite book of his is Swordwoman which contains the only three stories about a character known as Dark Agnes. It also has a tale about my favorite character of his Black Turlough. Conan, Solomon Kane, Bran Mac Morn, Kull, Cormac Mac Art, the real Red Sonja and the list goes on and on. He also wrote amazing westerns, boxing tales (Steve Costigan And Dennis Durgan are hilarious), oriental and middle eastern adventures. He even wrote Cthullu stories (which I prefer to H.P. Lovecraft). If you want to know more about the man check out the movie The Whole Wide World.