Matt,
First, all the mormons I know are very sweet people.
So you should treat them very kindly, and with respect.
Second, their beliefs are not considered orthodox by any orthodox denominations.
Third, none of them know anything about the masons, or secret societies. If anything they believe seems similar, the members know nothing about it, and will think you're crazy if you mention it.
Fourth, there are lots of orthodox books written about mormonism, explaining both their theology and history.
You should probably continue your reading.
Fifth, I'm sure there are some mormons who frequent CC. Even though I disagree with their theology, I recommend you be polite to them. They'll probably show up in this thread to defend their beliefs.