Commerce File is packaged for download at http://drupal.org/project/commerce_file.
Learn more at http://drupal.org/node/1356212.

Install
  - Place the entirety of this directory in sites/all/modules/commerce_file
  - Set your private file system path at admin/config/media/file-system.
  - Navigate to administer >> build >> modules. Enable Commerce File.

Recommended modules for use with Commerce File
  - File Field Sources