Re: How do I get dual sabers?

create new character
Light side Jedi ---> Knight ---> Sentinel (dual sabers) 
if you chose Guardian - they are single saber
if you chose Consular ---> Shadow - they are double bladed (saberstaff)
if you chose sage - they are single saber

same for dark side
Dark side ----> Warrior ----> marauder is dual sabers
Juggernut is single saber
if you chose Inquisitor -----> assasin is double bladed (saberstaff)
or sorcorer is single saber

other classes are not jedi therefore dont hold lightsabers.

after creating your character - it will still start with a single simple weapon not even a lightsaber. 
after a bit of story progression you'll be able to equip another weapon (if marauder or sentinel) or whatever the class uses

if you press C to bring up the character screen you'll see main hand and offhand
for sentinel and marauders offhand is for a second weapon. 
after unlocking lightsabers (story wise mostly) you'll be able to equip lightsabers in those slots.

no character begins with 2 lightsabers as a lvl 1.