Alfred Music Publishing The Zen of Screaming

I found this very helpful for training my voice over time. The included exercises are helpful as warmups and every-day vocal maintenance, and her personality is entertaining. The DVD itself, I felt, was lacking in substance, but maybe this has been supplemented with the later DVD.

I would not recommend this to those who have never sang (or screamed) before, as vocal lessons or other training would lay a stronger foundation for performance over the course of your life. She does not thoroughly explain the use of diaphragm and some other concepts, but puts them in Lehman's terms quickly. For people who already have experience/training with singing or screaming, this can be a valuable addition to your practice routine, although some of the warmups might be quite familiar.