Wow, I go away for a few days and come back to a bunch of crackpot theories. Really guys? Kill Belial with the Oar and drop the Clipper (which is reference to something completely different) beside a 6 toed statue and then run across the map to a random ambient lighting lampost and try to break it? What the !@#$?
No. No. No.
Lets go back to the roots.
We know we have 6 pages.
We know the first letters spell out DHARMA.
We know the ledgers speak of the captain getting away into the desert and never being seen again. In Lost, the captain was buried somewhere near the shipwreck as noted by the blast door map.
In LOST, the ship shipwrecked ON THE ISLAND because of those unlucky numbers. This could mean the Shipwreck in Diablo 3 crashed in the stinging winds because it was BROUGHT THERE by the numbers, or it could mean that the Black Rock Ledger may provide co-ordinates to an island (because that was traditionally the only thing that did provide co-ords in the TV series).
Or, it could be an easter egg that does nothing - but I find that hard to believe considering how it takes up 6 slots in your inventory and is trade-able.
So lets focus on what we KNOW. Lets look at what we HAVE and stop thinking about treasure goblin portals, random normal weapon drops in game, NPC followers and the staff of herding. We have absolutely no reason to believe any of this would correlate with any sort of secret LOST level.
OH - One more thing. if you're reading this, and you work for blizzard, please wipe that smirk off your face and give us SOME SORT OF INSIGHT into what the heck is going on. Any sort of reply would help us out.
Currently the best theory is a place inside the Black Rock Mines where a path leads to a door with a cow skull above it. The door cannot be opened, but apparently the map zone changes from Black Rock Mines to Stinging Winds EVEN THOUGH there are several zones between these locations. This is leading us to believe these zones may be linked by a secret entry somewhere.
Also, if you are testing theories, try and test them on Hell difficulty. It may not make a difference, but there's several references to Hell - one being in the ledgers themselves, and one being an entire notion surrounding the TV series that they island was Hell.