The current version of Visio is Visio 2007, so if you need to acquire Visio
2003, you will have to look on Ebay or one of the other sites selling used
software. If your version of Visio is one of the ones released by Microsoft,
then you qualify for an upgrade to Visio 2007. Anything released by Shapeware or
Visio Corp does not qualify.
I do technical support for Visio and have nothing to do with the marketing side
of Visio. So other than relay what I have said, I cannot go any farther.