Are 2nd hand telegraph/transmission poles available? A pole barn frame!

Sink 6 x 3000mm (10') lengths of them 600mm (2') into the ground, with a good lashing of old sump oil and creosote around the bottom afore setting in with rammed rubble and some sloppy concrete. They'll never move or rot in your lifetime and you can attach your base, walls and roof to them.
I know that to some this is "Hazardous Wood"!

Regards, Bill