I am ony a beginner but I know that you can put a redirection on under domain names to make your new domain name point to the old site.

The only probem I had with this was that it did not seem to be so search engine friendly.

So I actually ended up copying each page over from the old site to the new site by just copying all the code for each page in text editor, after I had set up the initial pages in Website Wizard first.