Ill save everyone the hassle trying to find the NPC to kick things off, if you are going rebel. Look for an NPC named Sheri Ray (Rebel Informant). She will have a rebel icon next to her name, and is located at /way 4892 -4844 Moenia. The Imperial informant will mostly likely be in Kor Vela, I will get a waypoint when I do the imperial quest on my other toon.