You get Kalem automatically (can't miss him) when the Ternie Kidnapping arc is resolved. Alexandra... that would be the NESF storyline. You should have some other mission to complete first before you find out where to proceed - check your mission log.

Actually all storyline paths go through this (Ternie being kidnapped). I don't remember what other missions you have to do in the NESF but you do have some other things to do first before the story brings you back to find Ternie.