How do I know a slin pin?

I am new to IGF. Know its time to get some pins, all I have of course is reqular points for gear. WHat do I look for and where can I go. What gauge do I want, lenth. That sort of crap. Help me out.

29Gauge, 1/2 Inch, 1 ml.

are you going to be shooting it IM or SubQ? I would recommend going IM but as long as your bodyfat is low enough you should have no problem using a 29g 1/2"