NFS is really easy to use.
Lets assume the server has an IP of 192.168.0.1
If you are running RH, as root
Edit the file /etc/exports on the server
Add a line to the bottom of it like:
/WhatIWantToShare 192.168.0.2(rw)
Then restart NFS:
service nfsd restart
Then from the client computer (the computer with 192.168.0.2), as root type:
mount 192.168.0.1:/WhatIWantToShare /WhereIwantMyShare
And that is it...
This is an extremely simple setup of it. More in depth setup can obviously be done. Here is the link to the doc that I used when setting it up.
http://www.linux.org/docs/ldp/howto/...WTO/index.html
As for NIS, that is a but less intuitive. Here is a link to a doc that can help you more then I can describe.
http://www.linux.org/docs/ldp/howto/...WTO/index.html
I hope this helps you.