Where is the old version?
The previous version of NameStation has been decommissioned, all features have been upgraded and are available on the new site. If you're missing anything specific, please tell us.
There are a number of reasons why we can't have both sites online simultaneously - mainly because the old one was to expensive to maintain and develop. Also, this kind of domain search requires a lot of resources and the continuously growing user base meant that timeouts and errors started to occur quite often. We can't have the old site consume these resources if we want to position NameStation as a high-end domain search service with constant availability. The new version shouldn't have any such issues.
We realize that the new version may not yet be as refined as the old version was, but there should be plenty of advantages that the previous one didn't have. We don't have any immediate plans to bring it back, instead we're focusing on continuously improving and adding new features to the new site.