If you have a hard time with treadmill interval workouts that tell you to run at "speed 9 at 6% incline for 4 minutes," try this 25-minute workout (including warm up and cool down) designed for the beginner runner.
Fat Burn Treadmill Workout. This is great since I have injured my heels and can't run right now. FYI, I did the math because a treadmill doesn't factor intensity into the calories burned estimation: a 150-lb person will burn approximately 450 calories doing this workout. It also ends up being 2.9 miles. Perfect!