how do i get that one signature...?

player made sigs o.o

make one or have someone make you one :P

Please look in the fanatics section, you may find artists who are offering to make signatures for free, or some advice on how to make your own:

http://pwi-forum.perfectworld.com/forumdisplay.php?f=122

do a screenshot of your char ingame, then put that in your sig
i dont know exactly how to do it, but hit the print screen button to take a screenshot("prnt scr" or something like that on some keyboards)

you could get someone to draw something for you too, which might look better, like spoons suggested