When I am cooking something that asks for milk, I tend to make a cup of Non Dairy Creamer and in every circumstance I have used it it has worked great! I bought a 16oz. jar of NDC for less than a dollar over a year ago and I still have half a jar left.
Where we are, powdered milk is WAY more expense that “real” milk. What are you using it for that might justify the higher cost? And yes, at our grocery store it's on the baking isle too – sometimes tucked in with the pancake mixes.