Ajax live users search?

I am looking to incorporate a ajax live search for the admin purposes for searching users so as soon as 3 char’s are typed it starts populating users. I want to use it in a custom admin template (which I already use for other stuff) so its not showing the default screen you see when you go to “Users” via the admin nav. I couldn’t find anything that exists for this or similar, only for front end.

Any ideas on connecting the dots? I know were not supposed to do direct DB sql queries. Wondering what wp functions and hooks to use.