Having read through the top 30 post on the linked page and found no infomation that would attually help people get the item i am going to reply.
GEB's drop in Nagafen's liar past the magma pool. you will need 3-6 50+ or 1 tank + healer 60+.
to reach the camp you will need to fight 6-15 sonic Bats,3 beetles, 5-6 fire imps and 1-2 fire elementals. you also need to go right around the lava pool not left as there is a 'pitfall' trap.
holding the camp is easy if you can get to it and it consists of 3 spawns 1 of which is a placeholder for Djinn. he also drops Djarns Amethyst ring <+9 Agil +80 Hitpoints>