University of California
Ucmp: Introducing Crinoids
This site from University of California is an introduction to crinoids with pictures. Click on another link to learn about the history and ecology, fossils, or morphology.
Other
Black Hills Institute of Geological Research, Inc.: Crinoids
Site provides a detailed overview of crinoids, more commonly referred to as "sea lilies" and "feather stars." Content includes a focus on the animal's endoskeleton, feeding, commensalism, habitat, value, forms, and more. Also has great...
Tree of Life Project
The Tree of Life Web Project: Crinoidea
This site from the University of Arizona provides a very thorough information on chrinoidea, including diagrams and pictures.
Other
Wet Web Media: Crinoids
A great site on everything you need to know about crinoids, including species, types, environmental conditions, ecosystems, and pictures.