Red Hat allows for 'driver disks' to be loaded during an install in case there is no out-of-the-box driver support for a specific piece of hardware. Basically, a driver disk is an ext2 disk image which can be created in the following steps:

Create Driver Disk[edit]

 # Create a blank, 20MB image
 dd if=/dev/zero of=driverdisk.img bs=1M count=20
 # Format the image with ext2
 mkfs -t ext2 -q driverdisk.img
 # mount it and copy the files over
 mount -o loop driverdisk.img /mnt/driverdisk
 # copy drivers to /mnt/driverdisk, then run
 umount /mnt/tmp

Once you have the driver disk created, you will need to tell the installer to load it by booting into linux expert or linux dd from the boot loader.