add barcode facility

Need some help for this. The orders from my website are send by phpmail to my email-address. It are text-files, simple, good and informative. Now I want a barcode on the order. For that the confirmation of the order must change to html and you have add a barcode* to the confirmation. I add two files to this small project. Both files are found on [login to view URL] and handle that what I need. But I have no knowledge about implementation. So if you can do it (or you have a better solution), your welcome to offer. *) we want a standard barcode that can handle nummeric and alfanummeric. For example UCC/EAN128 or code 39.