thats right you can get it in bone village, but only in Disc 3. tell teh man you wanna look for...either good or normal treasure (i forgot which one it was). Then DON'T set any workers up. Set up us the bomb (get it?). Then when he tells you to go to the spot you want to dig, go to the X at the lower part, above the crashed plane ( think it's a plane?) and stand right on top of the X. Tell them to dig there. You should get the W-Item materia eventually (after finding a couple of nothings or potions).
trust me i've done this.
