How can I drain an area easily? [duplicate]

Possible Duplicate:
How can I tunnel through water?

I accidentally flooded my mine. I am yet to find sand (early part of the game).

How can I easily clear out water which is about 15 deep?

Edit 2: This does still work, but you will have to log out after placing the solid blocks. When you log back in the game will not have remembered there was water there. This has only been tested in single player.

Edit:
The following no longer works as of 1.1.

LEGACY ANSWER:
If you place a block on an area covered with water, the water in that spot will be destroyed. You can eliminate the water by simply filling the pool with dirt or stone squares (you don't need sand) and then mining them back out again.

To drain huge amounts of water fast, drop down a Hellforge in a 3 wide, 2 high box under all the water. The Hellforge will prevent the lava from turning into obsidian when it comes in contact with water, but it will still evaporate the water. When building this evaporator unit, start with a 5 wide, 4 high box full of dirt. Then, hollow it out, and fill it with 6 buckets of lava. Then, drop in the Hellforge and open up the top. The result should look something like the graphic below.

WWWWW
DHHHD
DHHHD
DDDDD

W = your huge water volume
D = dirt, or whatever solid block you want  
H = Hellforge, flooded in lava  

If you don't have a grappling hook or other way to pull yourself out of the water for breath periodically, the easiest thing to do is probably to dig a parallel tunnel somewhere, until you can get UNDER your mine at the lowest point. Then dig someplace for the water to drain, then connect it to the mine and you should be clear.

Annoying, but easier than running out of breath trying to mine slowly underwater.