I looked for a link on a different SE site (Super User) and its Meta, but didn't find it. I had to search the web. Is there a link I missed?
Note: I found this site via a web search. But I would expect a link somewhere on all of these sites.
Most people are not supposed to find this site - they are expected to post on the child meta of the site they are on.
Most users do not need to know about the larger network and going through their site-specific meta should be enough.
It's the first site listed under "Other" in the footer.
Specific posts are also frequently linked in the side bar. ("Featured on Meta")