The most prominent organization of Mercenaries in Aht Urhgan, or at least it looks that way to a player character. You join their ranks in Aht Urhgan Mission 3: President Salaheem. The leader of Salaheem's Sentinels is President Naja Salaheem, a Mithra of doubtful manners and business policies. Recently Salaheem's Sentinels have been hired by The Empire of Aht Urhgan for a large scale deployment of mercenaries to aid the Imperial Armies.
The "secretary" who runs the day-to-day affairs of Salaheem's Sentinel's is Abquhbah. From him, you can learn all of the necessary requirements of a Mercenary.