I've not managed to do this either (Win XP Pro) via the floppy route.
The Intel drivers from the Intel website simply don't work - you get a choice of SCSI drivers by default, none of which work. I then edited the ini file so that the SATA drivers come up first by default, which at least gives you a suitable choice of drivers, but I've tried them all and again, none of them worked.
The FS website only has the Intel management software package (not the core drivers), not much help really.
I haven't tried slipstreaming yet (that's next on the list of things to try) but at least I am building the slipstream from a working Windows XP (Home) on the Amilo, so apparently I can use the existing drivers from my Windows installation when I build the slipstream, rather than having to download them from somewhere. If I figure it out, I'll let you know what I did. Drivers are only small so I should be able to host them for a while.