DNS servers cache the results of a DNS lookup for a domain (hentzenwerke.com, in this case) for a certain period of time. When you go to a given website, the DNS lookup does not always have to go all the way to the authoritive DNS server for that domain...DNS is a distributed system. So even if you have never been to a certain website, but someone who uses the same DNS server as you has been to a certain website within a recent timeframe, the DNS server you use will most likely give you an IP address that it is stored in its cache.

An nslookup reveals the following to me:

Server: ns1.worldnet.att.net
Address: 204.127.129.1

Name: hentzenwerke.com
Address: 209.67.50.203
Aliases: www.hentzenwerke.com

If you ping www.hentzenwerke.com, does it hit a different IP address than shown above?

>>You're DNS server must be using have a cached entry...
>
>Don't think so. I was able to hit pages I've never bothered to go to before.