Changing a DNS host?

The company that I work for has had IT services outsourced for a number of years. IT company also hosts our domain name, say example.com, but I'm not sure they host our website (we're trying to figure this out as well - this was all not setup or recorded very well before I came around). Now my company has been working me into being more and more of the IT person, and leaning away from said IT company (for a number of reasons).

We've come to a point where we do not want said IT company controlling so much of our network. They're taking quite a bit of control over it now that we do not use them for everything that I can do, to try to get more money from us. How do I go about asking them to release our DNS information for our domain, and once I have it, how would I go about changing to a different host (godaddy.com or others?) so we can control it? We own the domain name.

thanks

 

thats the thing - we have no idea who has that information. When you do a whois on the domain, my boss's email and our company info is in there and also the name servers it uses.

I guess we just need to ask them for all of this information.