Academic Earth has hundreds of lectures from professors and guest lecturers from Stanford University on entrepreneurship. There are a few bonuses as well, such as Guy Kawasaki discussing whether or not to get an MBA (get a technical degree instead). Here is a great short lecture about the best qualities of entrepreneurs.
There is a sub-category for social entrepreneurship as well. A lecture on the surge in social entrepreneurship is a good place to start. Do not be intimidated, these are generally not full length lectures. The videos I linked to are all around five minutes. I hope these inspire you.