I know about SysPrep for Windows, which should be used after installing a Windows image on a computer to make that computer unique on the network.
Are there any similar steps I should take if I'm using Linux? I have a lot of computers to install it on (identical hardware) and I would like to do it properly. Is there a guide somewhere or could someone tell me what to do?
Linux doesn't need the same sysprep/newsid usage as windows machines. Once you've installed the image, since there is no registry, you can simply edit a few files like /etc/hostname to change the machine name, then configure your network settings and you're up.
Redhat has an automated network installation system named KickStart which allows you to PXE boot the bare metal machines receiving the install, and then push a pre-configured image to each machine.
Similar systems exist for most of the major linux distributions. They mostly consist of a dhcp and tftp server to PXE boot the machines, a boot image that pulls down the install image/packages, and a config script that sets hostname and other information per machine.
FAI may be a great solution for you.
Fully Automatic Installation: http://www.informatik.uni-koeln.de/fai/
some time ago i've asked a bit related questions about management and cloning. since then i'm using debian pre-seeding combined with puppet and i'm quite happy with it.
if you will end-up cloning - make sure you at least re-generate ssh private keys for each machine...
In addition to changing the network config sure you remove the udev MAC-address-to-NIC mapping in /etc/udev/rules.d/*persistent-net* - otherwise your new machines will come up with eth2/eth3 instead of eth0/eth1 - etc.
But kickstart/fai/systemimager/etc are usually a better solution.
