If you mean the rune stones for the history quest, they are actually books you read. Not sure where you find them all, though, I've only found one so far.
What Oxnhorse was calling rune stones (greyish bluestone) are actually teleport stones.
The rune stones are books, and I'm pretty sure this quest is just a GH version of the book quests for Wizard City and Marleybone (was there one in Krok? I don't remember).
If they are the books (which I'm not completely sure of, but this is the suspicion), then the runestones are near the areas of major boss battles that conlclude the storyline of different areas.
