Hi Bullet, welcome to the forums! If you're wanting to add admins to your xfire, the best thing to do is play for a while and see which admins you play with the most. After you get to know them and they know you, send them a Personal Message (PM) here and see if they'd add you. We have a lot of members and most of them won't add someone they don't know.
I'm not sure what you mean by xfire talk on the server... Do you mean using the xfire voice chat while playing? Or a voice chat feature in the game itself?