Where can I buy...

i go to a local landscaping company and pick slate for free off of their trash pile.
 
Man I never knew that there were so many possibilites. I did call my LFS and they sell slate at $2.50 a pound. But I will first try to go to a landscaping business to see if they have any pieces of slate that they don't need. Maybe get it for cheaper that way.
 
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