There is a Nor Cal web-site that offers Flintknapping supplies and instruction:

http://www.obsidiandesigns.com/index.html

They might be worth a look. Their location is not far from the Sacramento area.

They also list meetings and workshops which they are participating in that might be of use. (many are in the Grass Valley area)
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While I have long believed that I will never get old, I have come to the realization that sooner or later there will be more people younger than me.