Depending on the depth you wish to proceed on the topic you can (1) watch the shorter TED presentation Harris gave in February 2010, (2) then move to the second video Harris gave later that year where he was given much more stage time than the limited timeframe provided by TED and lastly (3), if you still want more, then I highly recommend picking up a copy of Harris's book, "The Moral Landscape: How Science Can Determine Human Values". I did and it is an amazing mind-expanding read. Two thumbs and two toes up!
Sam Harris – Science Can Answer Moral Questions
Sam Harris – The Moral Landscape