Tithing was first introduced after Joseph Smith first established the church. It wasn't heavily enforced, recommended, nor up kept until when the Prophet Lorenzo Snow came around. The Latter-day Saints were forced out of Illinois in 1846 and they migrated to a territory which is now known as Utah. They were able to live there for a while, after afflictions from the government about polygamy, the church became in debt. In the 1890's, the church was $2 million in debt, and the saints crops were dying because of a drought. Lorenzo Snow received a revelation about tithing, and he began to preach to the church concerning tithing, and promised them that if everybody pays a full tithe, the Lord will bless them with rain. A month after the saints began paying an honest tithe, they were blessed with heavy rains.
Tithing money is used in building new temples, church office buildings, family history centers, and church stake buildings and chapels.
Today, Utah is a florishing state, and many members in the state, the country, and in the whole world, are paying a full tithe so they can receive blessings and help in their troubles. I myself pay a full tithe and I have a testimony that you will be blessed if you pay an honest tithe.