where exactly are the tombs?

I want to try the arena there. Anyone have directions?

The Tombs of the Primeval Kings is a different PvP area- separate from the Arenas. If you create a PvP character, it will show up on your map in the northern desert area. If you're wanting to go there with an RP character, you can open it up through the exit from the Dragon's Lair outpost.

ok, where is the dragons lair outpost? I am at auroras glade lvl 16

You won't hit Dragon's Lair for some time. Don't worry, you won't miss it accidentally.