Chris May

Here is some stuff from ZoneEdit:
The "whois" information is often wrong, and should not be used. Go to a command prompt/console and enter the command:

nslookup -type=NS yourdomainname.com

If the response does not contain all of the correct name servers, then you should contact your registrar and have them fix it. - To check to see whether a particular server is responding, you can add the server name:

nslookup www.yourdomainname.com ns1.zoneedit.com

If the response has a bunch of 'root-servers' that means the server does not know about the domain name and is referring you elsewhere. - To look for a certain record type, like the "MX" record or the "SOA" record, you can use the parameter "-type=MX" or "-type=SOA".

nslookup -type=MX yourdomainname.com