I think this is it? Looks like I need to move the files anyway. Have never done this before so I wasn’t sure!
http://codex.wordpress.org/Changing_The_Site_URL
Thank you, James. The instructions in that section seem to be for changing domains AND moving to a new server. I am not changing servers. I don’t even want to move the files to the new domain (within the same hosting account) unless I have to. Do I have to do all that? I was kinda hoping I could get away with just changing the “site url” in the WordPress admin dashboard. 🙁 I will look again at the codex.