The liquid in the middle of a coconut is not coconut milk but coconut water, a delicately flavored liquid that can be drunk straight out of the shell or added to fruit juices. Coconut milk comes from the flesh of the coconut, shredded or otherwise processed to extract a thick, white liquid. It can be used in both savory and sweet dishes.
Coconut milk is sold in cans, in which form it is very easy to use. Coconut milk powder is coconut milk that has been dehydrated, and it needs to be reconstituted with warm water. Also available is canned coconut cream, which is slightly thicker and richer, and block coconut cream, which is used to thicken and flavor.
You can get a thin milk from desiccated coconut by soaking it in an equal volume of hot water and squeezing it through a muslin cloth.
** Asian Recipes