While I attend the Berkshire Hathaway shareholder meeting this week in Omaha, I decided I might want to see some LDS Church History sites while there. I talked with Susan Easton Black who told me there is a nice museum at Winter Quarters where Mormon Pioneers built temporary housing on their trek from Illinois to Salt Lake City. Also, there is a restored building at Kanesville, Iowa that has significance for Latter-day Saints, because that is where Brigham Young was chosen to be the President of the Church, 3 years after the death of Joseph Smith.
Susan also told me there is a temple near Winter Quarters with striking stained glass windows. There are now about 120 Mormon Temples around the world, up from about 17 when I was young. About.com has some info on Mormon Temples.