Link Grove

If you need information about whether or not a "shamanism" group trying to recruit you or sell you ceremonies is even remotely legit, this is the place to ask.  Use the search to find out if they are already listed and investigated, or post your question to find out.  You may find their posting about What the Senecas Say About Twyla Nitsch very interesting.  There are many, many other posts about why you should stay away from the people associated with her.  Here in Israel, we had a group "Core Shamanism" who was involves in some sexual shadiness with under-aged people.  We are still helping people heal from the damage they did, and still fighting their fakery.  They just changed the names and are still trying to infiltrate the spiritual communities here.

A good list compiled by Craig Chalquist, PhD of Norse and German deities, with an impressive introduction.  The descriptions are concise but respectful, and it's a good start for anyone who is learning.  You may also want to check out his work on terrapsychology.  This will be very helpful for those of you who are getting into the Ancestors and the environment, and why they are important to your spirituality and your witchcraft.