This tradition was founded by Raymond Buckland in 1973. It has a Saxon basis but is, in fact, a new denomination of the Craft.
It does not pretend to be either a continuation or a re-creation of the original Saxon religion.
Main features of the tradition are the fact that it has open rituals (all of them are published and available), it has a democratic organization that precludes ego trips and power plays by coven leaders, there can be Coven or Solitary practice and there is the reality of Self-initiation in lieu of Coven Initiation, if desired. Seax-Wicca is found throughout the United States and in many countries around the world.
For more information see "The Tree: Complete Book of Saxon Witchcraft" by Raymond Buckland.
(I was unable to find a website dealing directly with Seax-Wica, beyond the usual definitions here and there.)