Repoint My Server

I have tried to launch my website onto the Internet without sucess. Yahoo web hosting has told me my browser is pointed to another server and I need to have them point my browser to yahoo. The other server
is a foreign one, and I have no idea how my browser was pointed to them,
cannot reach them at the telephone they supplied( its disconnected) and am wondering if there is a way I can take care of the problem myself and
get my website on. Please help.

 

Do you know the IP of where your server is?

 

My primary server is pointed toward:
castor.entel.chile.net
My secondary server is pointed toward:
pollux.entel.chile.net
The telephone number given for these is:
011-56-360-6119

The primary server I should be pointed toward:
yns1.yahoo.com
The secondary server I should be pointed toward:
yns2.yahoo.com

Thanks