I'm using my web address www.wraithscomicjourney.com, which I registered on Dreamhost, with Tumblr. I used Tumblr's instructions and added
www CNAME domains.tumblr.com.
and www.wraithscomicjourney.com works just fine. But when I leave off the www, it errors out. I know when the site is fully hosted there's a box to check to add the www; how can I do this with just the DNS hosting?