I just hit this point in the book, and I made quite a few. Between the difficulty to identify some of the rare/unique items found in the first area of book 3, and just learning about how deep the situation goes, I think I wound up making around 25 notes, but those included some personal story reworking I did as well as some fun little notes here and there.
I'm running this online in Foundry, so it was easier to do than handing out physical sheets. With journal entries, it was a way that players could peruse them at their own leisure.
I made a Journal note with a journal page for each topic. I "encrypted" the topics by leaving the notes blank, with just a suggestion of what might be in the note - "The sketches on this page hint that it could have something to do with XYZ." Then, once they were ready to settle down and start decrypting, I would paste in prepared stuff after they spent the time to do it. I also rearranged the various thoughts so that they didn't give away too much, but lead into other notes so that they would use that to lead in more research.
Having just done it with my players a week ago, I do suggest that if you do handouts, instead of just reading it to the players, be sure to let whoever is doing this decrypting read and then summarize it to the rest of the group. My players had a lot of fun with the "I found ABC in this note" "OH! If ABC then that makes the part of my note that says DEF make more sense!"
It was a lot of work, though. I spent a LOT of time crafting and proofing my handmade journal entries as opposed to just copy/pasting from the sidebar. I want to say I spent a good 10 hours out-of-game on them. Between deciding what goes where, and how much to drop, and re-reading things. The decryption part lasted them about two hours of our gameplay session, between deciding what to decrypt next and sharing with each other and generally fuming over the implications as they peeled stuff back. Going forward though, they have things they can check for themselves instead of asking me "what was that thing on the note about ABC?" So that may save some more time.