Hi Ur, on making coconut milk at home and yes I also use the canned ones but guess what the real deal is much better. I have heard that some canned varieties add cornstarch to thicken the milk. Now the ingredients don't say that but most of these are exported and I am not sure how honest they are about disclosing the contents.
The water inside a coconut (green or brown) is to drink. The brown ones are drier and hardly have any water. You can by all means use the water to grind the coconut.
To make coconut milk is extremely simple. It is once you get the coconut shelled and cut into small cubes. I normally throw it into a blender with 2 or 3 cups of plain water. Blend it and then strain it in a colander so that you can squeeze out the milk from the fleshy chewy part. Keep pressing until all you have left is husk looking pulp.
I will sometimes reblend the husk looking pulp once more with a cup of water to ensure I get as much as I can out of the coconut. I don't believe in waste
Use this milk to make curries or any other dishes that you fancy. I am assuming italian food does not use coconut milk but hey you can always experiment right.
You can freeze this milk as well in an airtight container and use it later.