I think I stopped finding crafting guides after Act 1 and started wondering if I was missing something. There are a billion and one crafting materials, which means that finding any SPECIFIC crafting material is a near-hopeless task.
Some ingredients basically don't even exist at all. For instance you need Crab Claws to make a Peace of Mind Scroll. There are exactly TWO (2) crabs in the entire game, Han can't fetch them, and I've never seen them in loot.
In the late game I started deciding that I wanted to craft my own Fortify and Restoration and Frost Armor scrolls, but even after 4 acts of hoarding almost everything I saw, I could only make a couple scrolls.