I just finished reading this new book: Liv Ingeborg Lied & Brent Nongbri, Working with Manuscripts: A Guide for Textual Scholars (New Haven & London: Yale University Press, 2025). It is not a very long or substantial book (179 pages). I read it in a couple of hours on the train to London (and back again). It is very readable, with a good number of photos and illustrations. I think the key thing about it is that it is written as a basic guide for new graduate students, which assumes they've read some texts in a critical edition, but now are thinking about accessing manuscript resources for their research - but don't really know anything about actual manuscripts (see p. 6).
This book, as you can see from the official table of Contents, has chapters on Manuscripts as Artifacts (why looking at manuscripts may be interesting, as well as interesting discussion and definitions of parts of a manuscript book); Finding your Manuscript (how to use a combination of print and online resources to locate a manuscript of interest; and how to decipher the many ways the same manuscript may be referred to); Provenance (thinking about how your manuscript comes to be where it is and the variety of ethical issues which should be considered in researching and publishing on particular manuscripts); Getting Access (how to email a librarian, and other tips); In the Reading Room with your Manuscript (what to actually look for and how to behave around librarians); Back Home - What Now? (how to keep track of your notes and photos); Asking for Help (how to email senior scholars and ask for help); Publishing and Permissions (does what it says on the tin).
The range and scope of the bibliographies will I imagine help any reader - there are pretty substantial bibliographies for each chapter (I certainly marked up quite a few items to track down and read*); the actual discussion is sometimes pretty basic - but for that reason will be extremely useful for the imagined student reader. There is a lot of good advice here. If you fit the intended reader profile or have students who do, then I'm sure you'll find this book useful.
*Potentially, at some point in the future. Maybe to get a pdf and save it randomly somewhere on my laptop.