The best introduction to the Emerging (Emergent) Church-theology is to read Brian McLarens early litterature on the subject. In general "A New Kind Of Christian" (hmm, the title is deceptive), and "A Generous Orthodoxy".
He is a very good and entertaining writer.
The best critical introduction to the Emerging Movement however, is D. A. Carsons "Becoming Conversant with the Emerging Church". Dr. Carson also lectures on the subject (and other important ones) which you can find here:
http://pjtibayan.wordpress.com/2006/10/17/d-a-carson-audio-sermonslectures/
http://andynaselli.com/theology/d-a-carson-mp3s
Dr. Carson is a great speaker and scholar (probably one of the best there is today) and a warm Christian who struggle for the truth of the faith. I highly recommend that you listen to his wise study of the movement.
Concerning the Emerging Movement - it is really spreading rapidly - over the world. I believe it to be a venomous and deceptive teaching... David Wilkerson has spoken about the movement in 2005 (look at timessquarechurch.org for more details).
Sincerely Magnus
:-D
