Today we’re happy to share that we’re adding even more to the free edition. We’re removing all feature restrictions from OneNote 2013. Starting today you’ll be able to access the full power of OneNote on your PC, including these features previously reserved for paid editions:

• Password protected sections—Add a password to protect sensitive information.
• Page history—Easily see or go back to prior versions of a page.
• Audio and video recording—Take notes while recording, and easily jump to the relevant section later.
• Audio search—Search for a word in a voice or video recording.
• Embedded files—Insert Office documents or other files directly in your notebook.

http://blogs.office.com/2015/02/13/onenote-now-even-free/

http://www.onenote.com/download