I am in Missouri, just south of St. Louis. I am part Modoc myself, and that is why I was interested in their tools. The points I found online, were all obsidian, or appeared to be, but there was no unifying pattern seen that I could detect. Even the arrows posted here seem to have different style heads on each arrow.
The book listed covers that immediate area I assume. A search for the terms did not do anything useful that I could tell. Lots about geology, with a side mention of artifacts.