Generate a Barcode from Form Data & Submit Form Data to Database (for Views)
Have taken a look at these modules.  MERCI Barcode, Views Bulk Operations Barcode Select , Barcode

The first two are for Drupal 6 only so they will not work in a Drupal 7 site out of the box. If you save the files without installing them you can read the code and see what they did.  The Third one has a beta for Drupal 7.x, so it can be installed.  Feel free to borrow code to learn how.  

As for getting it to work together...we would need specifics to provide answers.  Ask about whatever your stuck on.