How do i add this?
 

Ok, when you post, under your avatar it shows some stats, like your rep, and post count... i created ranks like "Noob" "alpha member" etc and i want "rank: whatever" to display under there.

How do i do this?

here you go :)
http://www.vbulletin.com/docs/html/user_ranks

Thanks for that, but i have already made the ranks etc but they wont show up :(

You can either edit the template to have Rank: show up before the code for the title,

Or you can edit the titles to display "Rank: Noob" "Rank: Alphamember" etc etc.