After much hunting and then finally getting lucky and finding a used copy on Amazon, I finally got my hands on "Qabalah, Qliphoth and Goetic Magic" By Thomas Karlsson, published by Ajna Bound. Let me just say that it is one of the most comprehensive books that I have read on the Qliphoth and it stands as a modern classic along the lines of Kenneth Grant's "The Nightside of Eden" (which I am still trying to read all the way through).
In the book, Karlsson gives a brief history Qabalistic thought and practice. Exploring the various Qabalistic ideologies on the origins of darkness, and evil. He then explores at depth the history of the Qliphoth as a concept and dark Tradition. He explains each Qlipha in detail, and gives information on their roles in the path of Qliphothic initiation and the path of self deification.
The book really shines when it gets into the practical application of working through the Qliphoth, and working with the Goetic/Demonic spirits in ritual. Included are some stories from others of the path as they relay their experiences with certain Goetic forces. Although he does make it point to state that some secrets are withheld for initiates of the Dragon Rouge (Of which the author is the founder) that should not dissuade the serious psychonaut. The process of refinement through darkness is a personal one, and the secrets will be revealed through personal initiation. The book also includes a few incense blends to be used in Qliphothic and Goetic magick, as well as the obligatory tables for magickal correspondences. All in all an excellent read, and great reference material. I highly recommend it not just for students of the Left Hand Path, but for magickal scholars interested in furthering their knowledge of the Qabalah.
The Book is out of print right now so a bit hard to find, but a second printing is in the works according to the publisher's web site.