This isn't Family Guy, but it features a couple of the voice talents from Family Guy in Seth Green and Seth McFarlane. Robot Chicken from Cartoon Network's Adult Swim did special episode sending up all the Star Wars films from the original trilogy, and I found it on Youtube. It's also got people like Mark Hamill (Luke Skywalker), Conan O'Brian, and even George Lucas lending their voices, and all three parts are pretty funny. Take a look.
[ame="http://www.youtube.com/watch?v=jsKdoMlJUng"]YouTube - Broadcast Yourself.[/ame]
[ame="http://www.youtube.com/watch?v=tVmXxspQPwQ"]YouTube - Broadcast Yourself.[/ame]
[ame="http://www.youtube.com/watch?v=T50RqFLQ3CM"]YouTube - Broadcast Yourself.[/ame]