Tale of the Island of Coal
So one day, my friends, I was exploring when I found an island made out of rock. A small amount of digging revealed coal. A LOT of coal. In fact, so much that I reckon 2/3 of the island was made out of coal. (it was a fairly small island with a bit of clay and a bit of sand but mostly stone and coal)
I dug... and dug... and dug... until I had about three stacks of 64 coal. I'm not kidding.
And then I fell into lava.
That is the most coal I have ever found... even more than when I went spelunking.
I was so disappointed at my death at Coal Island I deleted that world and started again.
P.S. If you want to spawn near an NPC village use the spawn 'gimmeabreak'. It's quite a decent world altogether.

Although none of the picturesque floaty islands I'm into.