I asked at the mill where i buy my lumber but they grind all excess scraps etc up and send it to paper mills. I will have to contact other places. I need sawdust for the garden too.I get my shavings from a timberframer, or sawmill. They only use spruce and birch up here. .
free if you bag it yourself, costs money if you get it bagged. $5 for a big black trash bag full.