The InterNIC provides a lookup tool called whois which provides contact information and DNS server information at this link:

An alternate site is at:

To check the current DNS configuration, we suggest using a tool like the Network Utility (included with Mac OS X), DNS Expert (http://www.menandmice.com/), WhatRoute (http://crash.ihug.co.nz/~bryanc/), AG NetTools (http://www.aggroup.com), or any similar program that has an nslookup function in it.