standoffs and all hardware required to mount the mobo, drives, and such comes with the case. they will not be supplied by the mobo maker. there are too many different lengths of standoffs used in the cases (due to the way each individual case is made), as well as different thread pitches used (1 metric and one SAE are common)
I just built a computer this weekend with the P182 case. There were 9 standoffs pre installed in the case I believe.
For the record, my case is an Antec Nine Hundred, just built my dad's office computer with the more professional looking P182. I was amazed at how great that case was. Cable management was such a breeze, you literally cannot see any cable other than SATA. Much easier than the Nine Hundred. My one bugger with it was that my DVD drive mounts wouldn't 'snap' into place as the installation manual said they would...
Ok it took me a few tries to find, but one review revealed that the accessories were shipped inside the case. I never opened mine because the door was already cracked and fallen off so I just put it back in the shipping box.