eclectic Wicca is not so much a tradition as a movement or perhaps a loose grouping. Many Wiccans use the label eclectic to describe themselves. As Webster tells us, eclectic means "Selecting; choosing (what is true or excellent in doctrines, opinions, etc.) from various sources or systems; as, an eclectic philosopher."
So, eclectic Wicca draws from the other traditions within Wicca as well as other sources to create a whole that appeals to the individual Wiccan or Wiccans involved. Many eclectics are solitary practicioners of the Craft. However, eclectic Wicca can often be found when you have people from different traditions that want to perform a ritual together (whether due to lack of others of their tradition there or as show of pagan pride). Such rituals are often a compromise for all involved.
Since the eclectics have no real leader per se, I have no direct sources -- just lots of bits and pieces of reading. If you want more information, go to The Witches' Voice and look around.