The eLearning Atlas is a comprehensize free list of elearning and LMS providers - brought to you by Rustici Software, LLC. One interesting feature is the ability to select a product type and then narrow down the choices to those who have specific specification support - such as authoring tools that support the Tin Can API. The list is being updated on a regular basis.
Check it out: http://www.elearningatlas.com/
