Domain Mapping not showing in Tools

I was reading through the configuration and have a couple issues:
1. No domains show up in the Mapped Domains
2. When I go to each site in my multisite setup and look under Tools, I can't find Domain Mapping

We aren't ready to launch yet, and therefore its possible I don't want to yet map the subdomains to their own domains, but I'm trying to prepare and understand what I will need to do in order to have each site in my multisite set up have their own domains (and I'm pretty stuck right now).