Well, if you wanted to research missing person cases you could start with the Missing Persons Discussion
. There's over a hundred pages with 20 different cases on each page. And those are just the recent cases.
If you're interested in historical cases you could look at the Missing but not forgotten Discussion
Families of missing loved ones need your help to bring them home!
They're grouped by decade and there are thousands of cases.
If you are interested in a certain person and you know their name you can see if there is already a thread by using the search window at the top right corner of each page.
If you are interested in unidentified human remains The Unidentified Discussion is the place to look.