recommend: buckwheat pillows
after trying many different pillows over the years, i settled on a buckwheat pillow. it is not fancy like memory foam. it's just a pillow filled with buckwheat hulls. it can be shaped and is firm enough to support the neck in different sleeping positions. it feels cool and refreshing throughout the night.
for people with neck pain/stiffness issues, i strongly recommend this type of pillows. there are many selections on amazon.