One bonus thought is that you just helped create a "right" way to play by listing out all the items such as spells. If, for example, a mage wanted to get every spell in the game, but there are some scrolls missing from the world....that would let them know what spells to pick to learn versus which ones they can just transcribe later.
I noticed "jump" is not listed in there, so now I know to learn jump as I level and just loot the magic missile scroll and transcribe it when I get it to fill out my spellbook.
Well, the thing with that is, a lot of the loot is randomized in this game. I mean, all the big items are always in the same place, but the contents of every little crate and barrel are not the same every game. So things like the scrolls are not always going to be the same ones, in the same amounts, every time. Just because I found a scroll of Blur, doesn't guarantee that you will.
Also, I did sell some scrolls, and scribed a few into Gale's spellbook. So it's possible that I did find a scroll of Jump, and scribed it, and then never found another one, so it's not on the list. I can't remember for sure. I definitely wouldn't have sold any Jump scrolls though, as it's pretty much my favorite spell in the game. I sold all the Speak with Dead scrolls I found, and there were quite a few, because I already had an infinite Speak with Dead amulet. There were a few other spells that for whatever reason I felt I would never use, so I sold those too. I did keep the vast majority of the scrolls I found, "just in case".
So anyway, that should not be taken as a definitive list of exactly what scrolls you can always find in the game. But it can give you an idea of how rare certain things are relative to other things. Like, I found roughly 50 Thieves' Tools. So that means they're pretty plentiful, and you probably don't need to worry about losing some. I found about 35 Alchemist's Fires, but only 5 Acid Vials. So if you're wondering which one of those you should hold on to, and which you can "waste", go ahead and burn (no pun intended) the Alchemist's Fire, because they're a lot more plentiful. Use all the Basic Poison you want, but be sparing with the Arrows of Darkness. That sort of thing.
I mean, most of the stuff I found, I didn't use at all. But apparently I should have, because there was so much of it available that I didn't need to hoard anything.