Whether you ordered a physical product or digital files, your bonus files are available in your Download Dashboard as a separate order. This will be listed in the order history, and you'll click on the Access Files link to the right of the product title.
You'll have to log in using the email address you used during checkout to access the files attached to your account history. Using the wrong email address has been the most common problem we've seen. Try a different one if you're unable to find the bonus files if there's a chance you might have used another email address.