OK will see if I can find a rubber place. Used to be a Clark Rubber near me but I think it's gone.
Re: the shelves. I went to Officeworks cos I'm lazy and it's 2 minutes away. I bought the 6ft high x 3 ft wide one for $99, it's got laminated shelves. I spent an hour and a half putting the damn thing up. But DIY and I are not the best of mates. I may have gotten distracted somewhere in the middle there. Anyway, my partner gets home and totally, I mean TOTALLY objects to the thing. "It's too big and we can't put the window blinds down." This is true. There's no way the window blinds can go down. So I rang Officeworks and asked if I could return them. The woman said yes, but I'm not entirely sure she was listening when I said that I had actually put the whole thing together and would now have to take it apart, possibly damaging it in the process. Ok I left out the possibility of damage part. Anyway, we'll see what happens.
I was thinking of getting the smaller unit http://www.officeworks.com.au/retail/products/Furniture/Bookcases-and-Storage/Shelving/OWPC1504. But now that Brett's said it bows in the middle I'm not so sure. Will see what I can find out about pallet racking. Sigh. This really seems harder than it should be.