I make my own. I is quite simple. Buy almonds, and peel them and place them in a glass of water over night to soak. Drain the water the next day and dry them in a dehydrator or in a very low oven.
Now put them in a blender and grind to a flour or you could buy almond flour.
Take one cup of water and put in 1/8th cup of the flour and blend for one minute. You have almond milk.