Any video recommendations of good public speakers to learn from about giving a speech?

Any video recommendations of good public speakers to learn from about giving a speech? I have a "Principals of Effective Speaking" class this semester at college where we have to do three speeches between 5-8 minutes and I want to practice and have some kind of example to emulate. I like TED talk videos but are there any other good ones you know about? I did a really short intro speech a few weeks ago but it went pretty badly even after I practiced different renditions of it over several days. :/