Non-Gmail users will not have automatic contacts with which to share items in Google Reader. To add a friend, click Sharing Settings on the left side navigation menu. It will say, “You are currently sharing with your chat contacts.” Because you don’t have Gmail, you have no chat contacts. Click Change. On the pop up screen select Share with “Friends” and save.
Now you can add friends by their email addresses. Remember, those friends must be using Google Reader to see your shared items.