Check out the latest numbers on trade from the Census Bureau. 

In 2009, the US put a new tariff on Chinese tariffs.  Was that a good idea? 

The Cato Institute, a Libertarian think tank, offers a large collection of articles making the case for free trade here.  

The liberal watchdog group Public Citizen's Global Trade Watch is broadly critical of many recent free trade agreements.  If you're interested in exploring anti-free-trade arguments, this is a good place to start. 

The World Trade Organization offers a page designed specifically for students interested in learning more about the organization and its role in promoting global trade.