Website Recommendations
Essays by the Church of Jesus Christ of Latter-Day Saints addressing challenging and controversial topics on church doctrine and history
https://www.churchofjesuschrist.org/study/manual/gospel-topics-essays?lang=eng
Many topics are listed and covered here: Blacks and the priesthood, the Book of Abraham, Polygamy, Women and the Priesthood etc etc.
A wonderful response to the incredibly destructive collection of poorly researched and largely debunked attacks on the Church of Jesus Christ of Latter-Day Saints
A massive website providing answers to almost every challenging question that has ever been presented by those attacking the Church of Jesus Christ of Latter-Day Saints.
Sarah Allen's detailed and documented reply to every section of the CES Letter (Reddit publication)
An incredibly detailed response to every claim in the CES Letter. 800 pages of excellent rebuttals to the tired old list of anti-Christ rhetoric that has been making the rounds for many years in many forms. You can spend hours perusing the very well annotated and explained responses to the many claims made against the Church of Jesus Christ of Latter-Day Saints. One of the best resources you will find to debunk anything found in the CES Letter.
Concerning Polygamy and the early Church of Jesus Christ of Latter-Day Saints
These two resources include almost every known source and faithful explanation on the topic of polygamy or plural marriage as instituted by the Lord’s prophet Joseph Smith.