You can buy unhomogenised milk at quite a few places, usually its organic and the cream sits at the top.
You can make yogurt from "normal" pasturised, homogenised milk as well as from powdered milk. Its extremely easy if you have an easy-yo, is super cheap too.
Unpasturised milk can be extremely dangerous, you would want to be 100% sure of the hygene of the source before you drank it.