Where Do I Turn In My Tatooine Commendations?
Empire Merchant on Tatooine
Both the Empire and Republic Tatooine Commendation vendors are located in the marketplace of Anchorhead. The easiest way to find them amongst all the other NPCs is to just mouse over all the credit icons on the minimap until you find the NPC that you're looking for. Once you've found him, of course you know what to do from there. And, don't forget that in addition to the NPC on Tatooine to whom of which you're able to turn in your commendations too, you are also able to turn in your commendations to the Tatooine Commendation vendor on your faction's Fleet Station.
Before heading to Alderaan be sure to turn in your commendations! Alderaan is much harder than Tatooine and you'll need all of the help you can get.