I've seen many people with it obviously, but I don't know how to get it. Pls help.

what exactly do you mean, how to have a rank?

simply click the "matchmake" button on the bottom left when you're playing toribash, then youre put into a queue, once a fitting opponent is found youre matched with him in a room, in a best of 5 in different mods.
after you've lost/won you will have a rank, which you can increase by winning more matchmaking games.

i dont get it, there is no matchmaking button, ingame or in the server list.

what version of toribash are you using?

usually the button is there even when you're in freeplay:



and once you clicked it, this window should open up:

oh, i dont have it updated, can u give me the updater link or whatever it is?

you can download the standalone version here: http://forum.toribash.com/showthread.php?t=571054

but i'd recommend to use the steam version, as this one is always up to date : http://store.steampowered.com/app/248570/

okay, thank you!