Crumb wrote:
as someone said you can cover the HD hole with tape...
Just as a followup, I've never found tape alone to work well enough. The little switch-pin in a high-density drive will usually just puncture or dent the tape, rather than getting held down, and you'll sit there in DOS (or on your *NIX machine), wondering why it won't let you format it in the older, wider-track fashion.
Then, when you try using sturdier tape, then you discover that it screws up the way the disk sits in the drive, and you have trouble inserting/ejecting it.
So the ghetto solution I've found is to fold up a scrap of paper and wedge it in the hole before taping, which works long enough to copy over a cool demo or, one supposes, a 'terminal emulator' with XModem (or ZModem, or Kermit...) file-transfer support so you can use a null-modem link instead.
If you're serious about 'making your own floppies,' you could probably find some plastic, Dremel off plugs of appropriate size, and crazy-glue some 'patches' of transparency film over the top and bottom to hold it on.
But at that point, you may as well be on Google, and seeing who still produces and stocks 'real' DD media in this day and age; there must still be a demand for it somewhere in government, if nowhere else.