The Council on Hemispheric Affairs is known for its well-researched and cogent analyses of trends in Latin America. Its recent report, Negotiating a New NAFTA, describes negative effects of the agreement in each country, particularly relating the problem of rural unemployment to migration from Mexico. Oddly, in my view, the authors remain committed to NAFTA and free trade in principle, while showing very clearly its ill effects in practice.
The Maxwell Library at Bridgewater State University has a great new service that puts a lot of documentary films (varying links, up to one hour) online for instant use by anybody with a BSU username. One of the first short films I've found is entitled Harsh Reality: Mexico’s NAFTA Problem, a 15-minute piece that describes shortcomings of NAFTA a dozen years after its passage, particularly in the area of employment in Mexico.
My August post about labor conditions in Guatemala under CAFTA includes links to law-library articles describing NAFTA and other major trade agreements.