What was Brigham Young's teaching regarding Adam being God? I understand that Brigham Young, the second Prophet of the LDS Church, taught what is known as the Adam-God doctrine for much of his tenure as Prophet of the Church.  

What are the specifics with regard to this teaching and where is it recorded?  How long was it taught?  Is it still part of Mormon Scripture/teaching/doctrine today?
This idea spawns from a number of statements that Brigham Young purportedly made, both in public and in private. For example, he was recorded as having said something like this in the Journal of Discourses, but the LDS Church does not officially accept any of the Journal of Discourses or cite it for doctrine because of erroneous scribing and other things.

Additionally, it is evident that the original, doctrinal meaning of which Brigham was intending to speak, was lost from the time it was received by revelation from God to the time it was transmitted, or transcribed, erroneously.

Immediately upon understanding that many were confused on this teaching or idea, Brigham spoke again on the matter. Here, President Young reports that he inquired of this doctrine to Joseph Smith, his predecessor to the presidency, and, startled by the confusion from his statements, attempts to clear up some misconceptions.

Finally, on 19 Feb 1981, a member of the Quorum of the Twelve named Bruce R. McConkie wrote a letter to Eugene England on this topic, stating, 


  "Yes, President Young did teach that Adam was the father of our
  spirits, and all the related things that the [polygamous] cultists
  ascribe to him. This, however, is not true. He expressed views that
  are out of harmony with the gospel. But, be it known, Brigham Young
  also taught accurately and correctly, the status and position of Adam
  in the eternal scheme of things. What I am saying is that Brigham
  Young, contradicted Brigham Young, and the issue becomes one of which
  Brigham Young we will believe. The answer is we will believe the
  expressions that accord with the teachings in the Standard Works."


(Note that we must still be careful extrapolating context when the audience was a specific person, not the world in general. It may not necessarily be the official view of the LDS Church.)

Clearly, a human made an error, but never has this doctrine been officially an accepted part of LDS teachings. In fact, today (I know from experience), this idea of "Adam being God" is not tolerated in Church schools or settings at all.

Enemies of the Church (see this page for documentation of this controversial yet accurate term; also see comments) will quickly take a glitch in history and blow it out of proportion, which understandably will cause others to believe that the prophet taught this "for much of his tenure as Prophet of the Church." At this point, I think the mis-understanding is clear.

The Godhead is made up of God, Jesus Christ, and the Holy Ghost. Jesus Christ is the Son of God who lived, died, and was resurrected, completing the Atonement for mankind. That is the LDS doctrine on that matter, and certainly is the most central and prominent feature of Mormon doctrine.

(I have also used FAIR's Wiki page on this topic as a source here.)