nslookup are used to find what your server IP address is. Use windows DOS "Command Prompt" (click >Start >Programs >Accessories), when the DOS screen opens, at the prompt enter nslookup followed by the name of the domain.

Example: if your domain is mailsbroadcast.com enter; Nslookup [space] mailsbroadcast.com [press enter key] to display the domain IP address.

Notes:
The DNS server IP Address have nothing to do with the process of email message delivery. It merely serves to turn the IP address--a series of four 8 bit numbers, ie: 151.196.75.10 into www.miyysite.com  (a domain name) that's all.

To get a DOS prompt in Windows 2000 or XP,
go to >Start >Run and key in CMD and click OK

DNS (Domain Name System) is a distributed domain based naming system database that can be query to identify administers of IP Address--which is a string of numbers, example:

207.151.159.3 are translated into a string of "letters" called Domain Name  - example:
207.151.159.3 = Domain Name www.internic.net

Normally when we send an email or browse/surf the internet we uses character string to specify a destination, like; www.mailsbroadcast.com or service @ mailsbroadcast.com but the machine on the internet does not understand this name (character string).

The machine uses a protocol called IP (internet protocol) and numbers like these; 132.0.33.54 to represent a destination, which is not very user friendly, therefore, a special internet service called DNS (Domain Name Service) is to help convert character string (name) into numbers.

Every email domain or website URL has their own individual destination number that is different from another.