I haven't worked out where you will be able to actually hire crew, but it will most likely be at planets. You can rescue them from many places though.
Crew are integrated into the inventory screens so that it is easier to move them around and see their info. I'm not sure you will ever interact with them through dialog.
Crew leveling is automatic. Your choice is whether or not a specific crew member is good enough for your crew, not how they level up.
Depths of Peril, Kivi's Underworld, Din's Curse, Drox Operative, Zombasite, Din's Legacy, & Drox Operative 2