you can do that by pinging the nameservers.....
Pinging NS2.FREESPIRITS.ORG [207.139.168.106] with 32 bytes of data:
I would say 207.139.168.106 is the IP address of thier server
No, that is only the IP address of the name servers the domain resides in. To be sure you need to query the name servers to find out where the actual webserver is located hence the nslookup on the web address.
You could in theory have 3 seperate parties, the domain host, the name server host and the web site host, although it is *usually* the case that the name servers are hosted by the same organisation as the web server.