Officeworks Bondi Junction had at least eight of these shelving units marked down to $7 on the clearance table near the front entrance. The website link shows $21.98 and they still scan at $21.98, but the in-store sticker says $7. Make sure the staff manually adjust the price to $7, otherwise they'll try to charge you the full price. They had to call a manager to authorise the $7 price for me, but it all went through smoothly. I went back later to buy another and they tried to charge me full price again, so I had to make sure it was marked down manually.
It's probably a manager's special so I can't assume other stores will have it at this price, but you can give it a go.
UPDATE: I scanned in the receipt, but it says 'Price Override-Soiled/Damaged' next to the item. I'm guessing this comment was added specifically to prevent price-matching at other stores. I'm not one to stop people trying though, so here's the receipt:
http://upload.ozbargain.com/2013/01/10/10387_officeworks_she…
I'm pretty sure last time I bought some of these shelves they were around the $30 mark when on special, so it's a pretty good bargain!
Steel 4 Shelf Unit Black
Simple assembly, with easy adjustment.
Dimensions: 710 x 300 x 1370 mm.
Weight Capacity: 50kg per shelf.
5 year warranty.
They also had a brown three box storage set marked down to $9 on the clearance table. Can't find the item on the website, but I saw them a few months ago for about $30. Worth a look if you need some small decent looking well built storage boxes.
Havent been able to get on to officeworks website all morning