Truth or Fables
Articles by ex-Seventh-Day Adventist, Robert K. Sanders, about why the teachings of Ellen White and the Adventist church are not in accord with the Bible.
http://www.truthorfables.com/

Former Adventist Fellowship Online
Offers forum, Bible studies, stories of leaving the Adventist church, locations of local fellowship meetings, and links to former Adventist groups and churches.
http://formeradventist.com

Life Assurance Ministries
Ministry to former Seventh-day Adventists and questioning Adventists. Excerpts from bimonthly magazine, many links. Exposing the unbiblical teachings and practices of the SDA church.
http://www.ratzlaf.com/

Apologetics Index: Seventh-day Adventism
Research resources on Seventh-day Adventism as seen from an evangelical Christian point of view.
http://www.apologeticsindex.org/s18.html

Catholic Answers: Seventh-Day Adventism
Explores the unbiblical teachings of the Seventh-Day Adventists from a Catholic viewpoint.
http://www.catholic.com/library/Seventh_Day_Adventism.asp

Seventh-day Adventism: A Catholic + Biblical Perspective
Site by Stephen Korsman examines doctrines of the Adventist church, finding that many have a "heretical and unscriptural twist" to them. Includes links to Catholic, Adventist, and anti-Adventist sites. Requires JavaScript.
http://www.theotokos.co.za/adventism/index.html