2013 and 2012:
http://www.nobelprize.org/nobel_prizes/economic-sciences/laureates/2013/
http://www.nobelprize.org/nobel_prizes/economic-sciences/laureates/2012/

click the name of the laureate you want to see, then click the "Prize Lecture", e.g.,
http://www.nobelprize.org/nobel_prizes/economic-sciences/laureates/2013/shiller-lecture.html

earlier lectures can be obtained same way (by changing the years).
the lecture for 2014 would come out in dec 2014.

还没看，但是非常感谢