I would like to do two things:
Set up a new site with a domain name etc (I know how to do this)
Also add my previous site to this plan (How do I do this?)
Very easy to do. You just set up the domain in teh pane, get all the files and whatnot set up and working (you can set up a mirror if you need to) and then switch the DNS of the domain to point to Dreamhost! it's as simple as that.
Here's a referal link
-->This explains more detail for you.
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