Not going to lie - I mostly downloaded this to see whether they had credited Kenneth Hite's "Bookhounds of London" from Trail of Cthulhu (they hadn't - but I recommend it for any game that uses books and booksellers.) (I'd also hoped to have some material for "Bookhounds of Greyharbour" - the d&d 5e homebrew setting we've been runnning for a while now that also uses Hite's work as a jumping off point.)
It's...okay? I like the two new backgrounds - Bookhound and Bookseller; and the Library of Korranberg as a patron is a nice idea, but it mostly feels like a lot of random dice tables. The "Using Books in Play" section is what I came for, and that's two-thirds of a page, mostly bullet points.
I feel like it barely skimmed the surface of a really interesting topic? There's some really interesting stuff out there about about the early printing trade, printers guilds and bookbinding that could have made for interesting plot hooks that I feel like it missed. For example, the section on informants felt like it could have been more book-focused, with just a few tweaks.
Nice images, though the artists aren't credited. I think the typesetting could be a little sharper - I dislike those chunky paragraph indents, there are some orphan words that some tighter editing could have solved, and the gp cost for books in the chunky list-o'-books titles could be in their own column, to make it easier to read, rather than wall-of-text.
Essentially - it's good for a $3 download and I feel like a jerk for nit-picking over something that cost the price of a coffee. I love books and ephemera and maps, and using them in my own games. I guess I was hoping for something more?