I never played it until the Warhammer edition, and from what I recall, they revised the rules a bit, so I'm not sure the versions are compatible. I think there was quite a lot released for that earlier version though.
It used to be a blind buy game. They had a couple different theme pack "flats", like their Midnight setting, and even Legend of the Five Rings. I sold those all a few years ago. FFG even had those available until 2010ish I believe.
I played one game of the vintage Diskwars. It was fun, but the ranged attacks felt out of place, as you would drop these little arrow tokens out of a tube from a certain height and hope that most of them landed on your desired target. And spells were weird, in that you had to pre-select the order in which your chosen spells would be cast during game setup. I might not be remembering this game correctly, at I played it in 2000.
A local game shop had Legend of the Five Rings Diskwars on clearance back around 2004 or so. I picked up enough of the base game and the expansion pack to run 8 different armies. Unfortunately, my L5R campaign had already wrapped up and most of my other gamer friends weren't interested in either Disk Wars or Rokugan.