Ouch!. 8"
disks are difficult to find, 5.25" disks are difficult to find
(what about 1.2 Mbyte ones - are they still available?), 3" disks are
impossible to find. I'd better start hoarding them... 
 You can still buy 8", 5.25" HD and 3" disks. Trouble is, they may be
 *Really*
  expensive; I noticed on the Imation web site a couple
of months ago that 
(from
  memory) a box of 8" disks was over US$100.
 3" disks are still available new from at least one place in the UK, 
though
they
  are over 2 pounds each. 
This sounds useful.  Do
you have any more information (like the URL of the
Imation web site) please?
Philip.