Users with ranks and information about them (ie permissions) are stored in <server root>/data/ulib/users.txt. They're stored in what I believe is a proprietary format, so you'll want to use ULib's tools to parse them and sync them somehow. Or at least analyze their code for doing so.
You could make things easier by using a ULib->SQL addon, but those are usually rather flaky. Use them with caution.
Honestly, the easiest route is just to make a static page with a staff list, and update it when a new user gains staff. Unless your server gets a new staff member every day or something (why?), this is the easiest way to do things.
