Sources for a Bookland and UPC decoder program that uses this device driver, and for all the programs listed in this article, can be found in the compressed file barcode.tgz available from http://www.seasurf.com/~jdennon/.
More information on Bookland and UPC bar codes, and a Python program that generates PostScript for printing a Bookland bar code with price extension, can be found at http://www.cgpp.com/bookland/bookland.py/.
All the software is GPL'd of course, as per usual, which means a number of things, including but not limited to, ``if it breaks you get to keep both pieces''.