Last Friday (May 23rd), you installed CentOS 5.1, a Linux distribution, on one of your two PC platform machines (and not on your Sun/Solaris machine --- that's the large blue machine on top of the desk that says "Sun" on it.)
This was done via a "NFS install" and a boot CD-ROM. Most of the configuration that you did after "linux askmethod" was to allow your machine to find its NFS server.
Yesterday (Wednesday, May 28th), you started making that new CentOS 5.1 machine a NFS server capable of providing the CentOS 5.1 distribution to your other PC.
In order for that CentOS 5.1 machine to serve as a NFS server for the installation media, you need to do several things:
Once you have your machine set up as a server, you need to boot the other machine with the same boot CD-ROM that you used to create the NFS server, and go through the same steps that you did last Friday, using a different ip number from your set of ten ip numbers that you were assigned.