The code you want for the SCSI card is available in the kernel already, so you won't need the external driver, the same is probably true with the network card, but I havn't looked...
To enable the SCSI card support you want to follow the kernel HOWTO, you can find it at http://www.linuxdoc.org/HOWTO/Kernel-HOWTO.html
Once support for the SCSI controller is in the kernel you should be able to access the devices hanging off it (assuming you've built support for them in the kernel too). It looks a little scary at first but isn't really that bad! It boils down to choosing the things you want, and then running
rm -rf /lib/modules/2.x.x/
Then you reboot... You might want to use make bzImage
if your distribution puts its kernel somewhere other than / (like /boot), if you do this you'll need to copy the new kernel accross yourself, you'll find it in /usr/src/linux/arch/i386/ once the compile is done. Note that the above doesn't make your old kernel available as a fall back, this is a good idea unless you're pretty confident that you've chosen the right bits in your config.
Have a read and post the specifics back, have a look in your kernel for mention of your network card too, it should be there somewhere.