People aren't talking about him because there is a conspiracy to prevent anybody aside from 2 approved democrat & republican candidates from being presented as viable candidates to the general public.
You're given the false concept of having a choice when really there is none since both guys are backed by the same interests.
Guys like Ron Paul and Gary Johnson don't serve those interests and therefore they get no media spot light and stand very little chance of winning an election.
It's not a conspiracy, it's the logical result of our election system. There are a million different ways to run an election, some of which encourage 3rd parties and some of which do not. Ours most definitely does not.
That doesn't make it bad, necessarily. Hitler came to power in a system that was more accessible to third parties--and is an example of how the weakness of these systems can be they allow radicals to take power.
Another example I read about recently was Abraham Lincoln, running for Senate, was something like 2 votes short of a majority (in the state legislature, which elected U.S. senators) and had a plurality, but since he couldn't get a majority he ceded the election to some guy who had like 4-5 votes out of 100.