For an authorative answer to your question please read this.

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Originally Posted By: FAQ
C. Are there other Satanic organizations which you endorse that might be local to me?

The Church of Satan considers itself to be the only valid organization whose goal is the dissemination of the philosophy of Anton Szandor LaVey. One can join regardless of nation of residence so long as one is legally an adult. We do not endorse any other organization and must warn you about the many pseudo-Satanic organizations out there: http://www.churchofsatan.com/Pages/Bunco.html

Also this essay by our current High Priest, Magus Peter H. Gilmore, explains our views about much that you might encounter while researching Satanism on line: http://www.churchofsatan.com/Pages/MythCommunity.html