Pair of years ago I had such addon, but now can't remember it's name. I just remember, that it used pack of /who requests to gatther information.

Anyway, that or another - help me please find any addons, that gathers information on levels and classes distribution on realm.

The only one I could think of is CensusPlus.  Then the data is sent to http://www.warcraftrealms.com/census.php

i used to have an addon that showed me stats of players like spell power and stufff but that was a long time i ago and i cant find the name.