How can I find out who is my domain name server authority

[sabo]

I have moved my server from one isp to another.  I need to change the
IP address that my domain name resolves to,  I dont have acccess to
the account that controls the current primary nameserver.

I have a domain name registered with go daddy.  I am trying to forward
that domain name to another domain name OR ip address.  The person who
set up dns on afraid.org took their login info with them when they
disappeared.  I am trying to change the dns settings but cant access
the account that has control of the current dns server at afraid.org.

How can I regain control.  I need to do a couple of things since I
moved my server from one isp to another.  I need to change the IP
address that is currently resolving to the IP address of the new isp
provider.    I tried to do this via the dns forwarder at go daddy but
that will not work since I have custom nameservers that I have no
control over.

So can I just change the primary nameserver to another.  If yes how do
I enter the IP address that I have been given from the new ISP.

thanks in advance.