I'm betting you get your response in email today. There was a hacking attack last night on DH, so they were a bit busy. I've been with DH for a long time, and I can tell you, they are the best. If you don't hear from them by this afternoon, contact them by using the email link on the front page http://www.dreamhost.com/ if you can't get to your web panel.
After your account is activated, it takes 24 to 48 hours for the name servers around the net to get their databases updated, so you probably won't "see" your site until that happens. But you will be able to build your site and FTP into it to upload your files.
zentao web design, graphic art and design at www.zentao.com
zentao7, Gallery of Artists and Speculative Novel Writers Groups