DNS Problems

The problem that I am running into is that I have 2 domains, I am sure there are more that I do not know about, and both are resolving incorrectly, which of course makes them unreachable.
I am looking and looking, but am unable to find out where the DNS gets it’s info from. When I do a query, where does my DNS server go to resolve the name? Kind of a basic question, but I am trying to find out why these are resolving incorrectly.
OS is Win NT 4.0.