I too swear by the buckwheat pillow. In fact I was so impressed that I saved up and bought one for my hubby and for each of my kids too(that is 6 altogether). At $50 each it was a bit of money to lay out on pillows, but I say worth every penny.
When I go grocery shopping or to public events, I wear my right arm (the side that is worse) in a sling that takes the weight off of my shoulder. It helps to remind me not to pick things up that are too heavy, and a visual for people around me.