I noticed this had changed a while back. I believe Dreamhost has recently changed some of the control panel, but they might have not updated the Kbase. All they did was take out a few tabs and combine them into other ones.
-everything in the web tab, I think was moved to manage domains
-to add domains just go to registrations
-And I think the IP tab has been changed to Manage Domains also
I think I'm correct, but if you find that I am wrong plz post here.