Weapon: His Poison Claws
Attacks:
Sesshomaru has claws, like our Inuyasha except, unlike Inuyasha, Sesshoumaru's claws are poisonous. He's used this attack on Inuyasha a number of times when they fight.
Weapon: Whip
Attacks:
Earlier on in the series, when we first see Sesshoumaru, he has a whip. I think he mainly uses it on his oni (the huge demons he usually travels with), but when he and Inuyasha fought for the first time, I think Sesshoumaru may have used it to fight with.
Weapon: Tensaiga (Heavenly Life Fang)
Attacks:
Tensaiga is the sword that is opposite of Tetsusaiga, which belongs to Inuyasha. While Tetsusaiga has the power to kill 100 people with one swing, Tensaiga has the power to save 100 lives with one swing. Sesshoumaru used Tensaiga to save the life of a little girl named Rin, and as the story goes on, he saves more people. ^_^
Weapon: Toukijin (Fighting Demon God)
Attacks:
Toukijin is a sword made out of the fangs of an ogre who broke Tetsusaiga. Sesshomaru commisioned the evil swordsmith, Kaijinbo to forge it for him. This sword has an extremely evil aura and is very powerful, in fact, it is so powerful that it managed to possess Kaijinbo. Sesshoumaru uses it like any sword, except, the sword's aura has the power to cut his opponents up.