This is not yet a Book of the Week… yet. What The Starry Wisdom Library: The Catalogue of the Greatest Occult Book Auction of All Time is is quite possibly one of the few absolutely-required supplemental materials needed for pretty much any Cthulhu Mythos campaign. The conceit is that it is a facsimile of a 19th Century catalog for the auctioning of the Church of Starry Wisdom’s occult library, which apparently had every significant book ever mentioned in the Mythos inside of it. What makes thus book so indispensable is that each tome inside it is physically and memorably described as a book; this gives it a genuine ring of authenticity. It’s also a dry delight to read.
A must-have for Call of Cthulhu GMs looking to establish verisimilitude, or looking for a quick MacGuffin for driving his players mad.