International Association for the Preservation of Spiritualist and Occult Periodicals
The International Association for the Preservation of Spiritualist and Occult Periodicals is a group that maintains an open-source archival website www.iapsop.com with a massive database of scanned periodicals, books, and other materials. As of October, 2019, the database included at amazing 3.5 million pages, 36,021 files, and 516.9 gigabytes of data.
The organization is described on its website as:
An informal collection of students, academics and researchers with an interest in the periodical literature of Spiritualism and the occult, for the purposes of preserving the substantial body of Spiritualist and occult periodical literature produced between the 1840s and the start of the Second World War. These materials are provided in curated, digital form, already indexed, suitable for online reading, scholarly use and citation.
IAPSOP welcomes volunteers, financial support, and donations of materials. Users may download local copies of the complete holdings, which will be automatically synchronized with updates.
Hundreds of periodical titles are available through IAPSOP. For a current list, see this index.
The Standard Spiritualist and Occult Corpus (SSOC) is described as
an open source text project, focused on book-length texts, in English, covering Spiritualism, the occult, New Thought and allied parasciences (mesmerism, magnetism, phrenology, alchemy, chiromancy and so forth) published between 1790 and 1940. Currently the SSOC consists of more than 8,000 book-length texts (approximately 2.1 million pages), and includes many of the texts considered "classics" in Spiritualism and the occult. Every text in the SSOC is supplied, free of charge, in indexed PDF form, allowing it to be electronically stored, searched, printed and converted (to image, HTML or text). The outer, later bound of the corpus is limited by copyright law.
For a complete listing of books, arranged chronologically by date of first publication, see SSOC on IAPSOP website. Accessed October 24, 2019.
Private and Mail-Order Lessons
Another IAPSOP activity is available:
IAPSOP collects and publishes private lessons and teachings from occult schools and mages from time to time, as material is donated.