Linux – How should I install NFS on a linux system

I have two systems and I need to setup a folder on one of them that is completely read/write-able by the other.

Questions:
1) How do I setup NFS on the server(s)? It is not installed as an available filesystem/module.
2) Where should I place this folder / what is the conventional place for locating such shared folders?

This is a RHEL5 system.

Error with setting up NFS.

This is what I did on server1 on which I want to share a local folder with server0

1. In /etc/exports , I added
   /home/els1-share 199.199.82.98(rw,sync)

2. mkdir /home/els1-share

3. Enabled nfs and portmap through
   ntsysv

4. Started services:

/etc/init.d/portmap start
Starting portmap: [ OK ]

/etc/init.d/nfs start
Starting NFS services: [ OK ]
Starting NFS quotas: [ OK ]
Starting NFS daemon: [ OK ]
Starting NFS mountd: [ OK ]

Now, on server0, I did
1. mkdir /home/els1-share
2. mount 199.199.82.130:/home/els1-share /home/els1-share

which timed out with:
mount: mount to NFS server '199.199.82.130' failed: System Error: Connection timed out.

The IP addresses have been obfuscated, otherwise the output is exact.