>I'm not sure what you mean when you ask if I can use a 3 or 9 font. Can you email me at jcturner@sprintmail.com?

There's more than one barcode standard. 3 of 9 is one of the more common scalable barcode fonts. Your application requirements and barcode reader equipment will largely determine which of the several available fonts is most appropriate for your use.

I use 3 of 9 codes for many of my in-house applications; most of the commercial barcode scanners will be able to read 3 of 9, and it can be sized and used easily in our applications - we use it on our packing lists, and require cartons of new books received from the print house have a very large 3 of 9 barcode that identifies the contents clearly, and can be read from several feet away by the portable readers that we use throughout the building.) It's not the right choice if you're going to barcode envelopes for mail sent to the Post Office (there are very specific barcoding requirements available from the USPS; the DMM (Domestic Mail Manual) is the definitive document here), or if you're creating one of the special barcodes used by shippers like FedEx or UPS (they use different barcode fonts, and have different positioning and sizing requirements as well, which they document and require strict adherence and certification of output before they'll accept packages from you.)

You might want to do a bit of research on barcoding before starting to write your application.