House near Maevar's Guildhall, House in the Bridge disctrict, area in the sewers.
Ring of Gaxx
Restore Kangaxx's Body is a side quest in Baldur's Gate II: Shadows of Amn. It can be started in chapter 2, it's recommended to start this quest until the party has gained some levels and more powerful equipment, because of the difficult battles.
Descend the stairs and click on the sacrophagus. Kangaxx will ask you to retrieve his other body parts so that he may be freed from his eternal imprisonment. You need to acquire his legs and arms and torso.
Go to the Old Tunnels in the northwest corner and click on the sacrophagus in the north corner. Once you have defeated the lich who guarded the body parts, click on the sacrophagus once again to retrieve the Golden Arm and Leg. You will need to progress up to a certain stage in the side-quest Find and Destroy the Cult of the Unseeing in order to access the area. Gaal gives you a key.
You can find the Golden Torso in the building south of Delosar's Inn in the Athkatla Bridge District guarded by another lich.
Return to Kangaxx in the Athkatla Docks with the body parts and he will be freed. As reward, he will try to kill you for making the effort. First you must beat him in his skeleton form. After doing enough damage, he will take a demi-lich form. Defeat him and you will receive the Ring of Gaxx, which is very powerful.