Individual Family History Libraries or FamilySearch Libraries have very extensive and useful websites. Here are a few of the larger ones:
- Brigham Young University Family History Library
- BYU Family History Library Facebook
- BYU Family History Library YouTube
- Mesa FamilySearch Library
- Ogden FamilySearch Library
- Los Angeles FamilySearch Library
- Riverton FamilySearch Library
- St. George FamilySearch Library
Brigham Young University has a remarkably large number of valuable family history resources scattered around in their huge website. Here are a few of the more accessible resources:
- BYU Center for Family History and Genealogy
- Conference on Family History and Genealogy
- BYU Religious Education, Family History Lab
- BYU TV The Generations Project
There are two other FamilySearch websites not usually visited by researchers but with valuable information:
The Church History Library also has a lot of valuable digitized documents and resources as does the LDS.org website.
Also see LDS Archives and Libraries.
There are many other resources in the University libraries in Utah and elsewhere that you should investigate. Try searching for LDS history genealogy and see the results.