Currently Being ModeratedNov 13, 2012 1:28 PM (in response to xicano.power)
Try ebay. You could also try to get hold of a copy of the stand aloan OS X 10.4 (tiger) this will also work.
Currently Being ModeratedNov 13, 2012 1:52 PM (in response to xicano.power)
There are two types of disks available. System restore disk which would have come with your iBook when it was first purchased. These are normally gray and come in a set.
The other is a retail version of Mac OS X. Depending on which model of iBook you own would determine which version of Mac OS X you can install. If your iBook is greater than 800Mhz and has 512meg of memory, you could install Mac OS X 10.5 Leopard. These retail disks are are black and show a big 'X' on them. They are DVD's and can be brought from vendors like Amazon. System restore disk are a little harder to find, but can be obtained from some online apple spears. A replacement Mac OS X disk either retail or restore copies wont be cheap to buy.
Best of luck