setenv ide_maxbus 2
(use 1 if you only use one ide bus)
setenv autostart
setenv bootdevice 0:1
(boot from partition 1 on device 0)
setenv bootcmd diskboot
Assuming you have an Radeon card
setenv bootargs root=/dev/hda2 video=radeon:1024x800-8@70 L2CR=0x80000000
saveenv
ide reset
Insert your linux debian CD
diskboot 500000 1:0
(boot from partition 0 on ide device 1)
If it still fails get another iso image from ross's debian site.
Cant remember the url but its something line
amigaonelinux.souceforge.net

You should have been put on the dev list by your dealer.