After doing a bit of research I found a site that sells software that can print tags on plain paper. They include both the botanical name and the common name on the label. As a bonus, the family name is auto-magically tacked on.
Apparently you just laminate the labels and attach them to a wooden stake. They seem to be attractive enough without being too intrusive in the garden. The software is called The Compleat Botanica.
Erica