Back in the 80's I was really buying up the occult books. I was building up my library. The late Al Manning was a certified public accountant turned occultist. You can verify some facts in the Wikipedia. Some of the titles were Eye of Newt in My Martini..., Helping Yourself with ESP..., Helping Yourself with White Witchcraft..., Miracle Spiritology, The Miraculous Laws of Universal Dynamics and there may have been others. Many of my books were tossed out because I had strong Christian parents. I remember having the books and not remember selling them. Al Manning was a close 2nd to Geof Gray-Cobb when it came to authors. His book on Gnostic Magic became a model for my work with spiritual forces.
Al Manning was the founder of the ESP Lab of Texas. This was originally a mail order outfit until the internet came along. You can search Google to find the ESP Lab (leave the "of Texas" off) as they have moved to Colorado. They carry on well without Al Manning. They give you free lessons too. They can do a candle ritual for you or a more intensive magic for problems or needs.
I checked bookfinder.com to find out where Al's books are at for prices. I was surprised to find a few good bargains out there for the occult collector. My favorite book: "Helping Yourself with the Power of Gnostic Magic" is going for about $80. His New Ishtar is going for about $47 now, but the White Witchcraft has a number of sellers selling it for close to $3. That's one's a bargain. In recent years, I was trying to track down a miniature pyramid Manning designed to increase magical power. He mentioned it in one of his books. The pyramid seems to have disappeared and now there seems to be just a "pyramid exercise" mentioned at the ESP Lab.
Mr. Manning was a great author. Buy his books or check out the ESP Lab. It is worth it.