I listen to Alex off and on, and I've gotta admit his voice is annoying, and he yells a lot. That is very true, he has somewhat of an irritating voice.
He also goes off on rants a lot, gets very emotional, and sometimes mis-quotes articles and sources.
But the truth movement does actually have some evidence behind it. I know the common perception of '9/11 truthers' is the guys walking around yelling "9/11 was an inside job," and I can see how that would irritate some people. But the main reason the movement has so much momentum is because there are legitimate questions about 9/11.
http://journalof911studies.com/volume/200609/WhyIndeedDidtheWorldTradeCenterBuildingsCompletelyCollapse.pdfTake this report by Steven Jones, a PhD from Brigham Young University, that found nano-thermate particles in the dust from the WTC. I know, it sounds crazy, but it is what it is. Nano-thermate is only manufactured and used by our military, and is state-of-the-art.
Another question to ask would be "what brought down tower 7." This was the tower that wasn't physically hit by anything, yet collapsed in its own footprint at freefall speed in the late-afternoon on 9/11.
I'm just saying, although you may not like Alex Jones, or the truth movement, there are certainly legitimate claims behind some of what they say.