Having trouble locating 10% vinegar to use to kill my weeds. The shipping cost for purchasing this item is almost as much as the product itself. Any ideas or comments would be greatly appreciated.

Have you tried feed stores, and not just the big home centers with garden departments?

I went to the forum home page and clicked on "organic businesses" and got this list when I entered "California."

http://www.dirtdoctor.com/organic/garden/advance_business_listings/?proceed=1&searchtext=California

Are any of these near you?