This item is from the Yet Another Enhanced IDE/Fast-ATA/ATA-2 FAQ, by John Wehman and Peter den Haan with numerous contributions by others. (v1.92).
DriversHQ <http://www.drivershq.com> is one of the most well known sources for drivers.
In Finland, someone got the immensely useful idea of setting up a site with all kinds of IDE card drivers. You can find it on <ftp://ftp.funet.fi/pub/drivers/pc/disk/ide_ata>. If you can't find a driver here and manage to pick it up somewhere else, please upload it. Help making the net work.