Add extra info under postbit

[wAnBoA]

Hey guys,
I know that if you want to add extra info under the postbit all you need to do is to edit the postbit_legacy template.
etc

<if condition="$post[field3]"><b>Interests:</b> $post[field3]</if>

$post[crowns]$post[champtext]

But there are quite afew info i would like to add etc Profile pic, no. of thread made, last online, view user's thread, album link . . .

How do i actually find these code or whatever you called?
Can someone teach me how to obtain such code?
Thanks in advance!