Install Snow Leopard Over a Network

Help, please! I have searched and searched to no avail.

Snow Leopard server and Snow Leopard client machines. I want to install the same image that I created on one machine on to the other 25 on the network WITHOUT having to install that image from a FireWire drive.

I used the system image creator on the server but it would only let me create a 'netboot' image (created via Target Disk mode). Is that the wrong kind of image?

Also, I want to be able to update / add to the machines via the network instead of individually.

Can someone please point me in the right direction?