Probably the most important and controversial question to be leveled at the SDA church and it's various offshoots is: "Is Ellen White a Prophet?".  Clearly an answer of "yes" or "no" has many far reaching implications for the organisation of around 16 million members, yet the general conference seems to be content with producing lackluster DVDs such as "Prophetic Inspiration" that states clearly that she never claimed to be a prophet, among other outright twists of her writings.

Then you get the embarrassingly lie filled productions like "The Spirit Behind the Church", which seems to have been based on the book "the White Lie".  For those who have been duped by this video or Book, "Response to a video" will have you slapping yourself for being so easily misled.  I have seen media productions do some fairly blatant twisting of facts, but "The Spirit Behind the Church" breaks new records in dishonesty.

So now, here is a group of videos showing you why so many people in her time were convinced that she truly was the prophet, sent by God to raise up a people for the second coming of Christ.

Some Videos:

 - Mark Woodman - A Gift of Prophecy - Part of the "God's Final Call" series.

 - John Thiel - Is Ellen White A Prophet? - probably the most detailed and solid of the 3.

 - Walter Veith - God's Guiding Gift - Part of the "Total Onslaught" Series.
- Bill Hughes - The Puzzling Prophet

Some Articles on this topic, with supporting materials:

http://sabbathsermons.com/category/the-spirit-of-prophecy/

and more:

http://www.whiteestate.org/issues/contradictions.html - covering supposed biblical contradictions that Ellen White has made.

A Book:
Again, I can't recommend this one enough:
http://www.pickle-publishing.com/books/response-to-video.htm

God Bless you in your search for truth.