yo scythe, i had the same problem.
I tried downloading the files SEPERATELY and then putting them on a flop. This worked fine. I don't know why, but the bootflop ( bare.i ) on the slackware 9.0 cdrom just doesnt work ( i got same message ).
Go to the slackware site, click get slackware and then, when you have selected a mirror, do NOT chose for ISO, but just for SlackWare 9.0. You can download all the stuff you need there. Worked for me
Hope it works for you 2 ...