This book, while posthumously published in 1991 (Trungpa died in '87), actually dates to a series of lectures that he had done in the U.S. in 1972 dealing with the famed teacher Padmasambhava and the "Crazy Wisdom" approach to enlightenment. Chögyam Trungpa was, perhaps, an ideal figure to be introducing Vajrayana to the states at that time. A tülku, or re-incarnate Lama, he had come up via the traditional Tibetan monastic system, but at age 19 he had to flee the communist Chinese invasion, eventually, in his twenties, attending Oxford and there becoming fluent both in English and in the cognitive approaches of the West. Following this, he retreated to a period of solitary meditation at a monastery in Bhutan, an experience which dramatically changed him, as when he emerged from this period of isolation he opted to live as a secular person (as opposed to being a Monk), although still teaching. Soon after he moved to the U.S., married, and began his rather remarkable career of teaching, publication, and the founding of centers (including Naropa University in Boulder, CO). This book is an artifact of his early years here.
The subject of these lectures, Padmasambhava (the teacher who brought Buddhism to Tibet), is a remarkable figure, having eight "manifestations", each with a different name and attributes ... this allows Trungpa to break down his teachings into fairly easily-digestible bits, followed by questions by his students. The book is able, in this way, to transmit a great deal of the "crazy wisdom" approach that Trungpa sought to teach (along with his concept of "cutting through spiritual materialism") without bogging down in a lot of Tibetan technical terminology (although this is certainly referenced).
I was fortunate to be able to attend one of Chögyam Trungpa's lectures in the 80's, and he was at that point a "very complicated" figure. In his later years (he died at age 47), he was drinking very heavily, and was often (as in the case of the event I attended) quite late arriving for talks ... however, once in the "teaching mode" he was very direct, almost as though he was using the booze to "curtain off" all distractions so that what focus he had was purely on transmitting the dharma. Crazy Wisdom, however, dates from his prime, and I think it is the most accessible of his books (and I have read another half a dozen or so).
Unfortunately, it appears that Crazy Wisdom is no longer in print, so you're going to have to rely on the "aftermarket" sellers for a copy. The good news is that you can get a new copy for about ten bucks (half of the original cover price), a "like new" copy for around five bucks, and a "good" copy for around a buck via the Amazon new/used vendors. Again, if you have any interest in Vajrayana, I would recommend this book ... while it is not "official" Vajrayana the way that the Dalai Lama's The Opening of the Wisdom Eye is, reading it will certainly leave you less confused and a whole lot more inspired about what this path can accomplish!