Email notification based on purchased item
Have you tried rules? The trigger would be when new content is added, and the condition would be that the content type is appropriate. Not sure how you've stored the data connecting subscribers to their magazine, but that will be needed for the action. I don't think you'll be able to do this out of the box (specifically I'm not sure if you can send an email to multiple addresses using rules) - so you might need to write a custom action.