It may be that as a PayPal account it could take longer. If you come from a region of the planet where there have been payment problems it may be a case that your sign-up is being dealt with manually, and as it is the weekend you may have to wait for the business week. I am just guessing at this. I used a CC and it was all set up within about an hour.
It may be that the server dealing with sign-ups is perhaps a bit sluggish and your request is in the queue.
Once you sign up you can make purchases from the ControlPanel billing section and make your payments that way.
You may want to send a message to the sales department via http://www.dreamhost.com/contact.cgi
just in case your sign-on got lost somewhere.
Opinions are my own views, not DreamHosts'.
I am NOT a DreamHost employee OK!! :@
You act on my advice at your own risk!