So I was able to implement your code and suggestions and things look really nice!!
However, one small problem...
I have pages with buttons on them that are not currently associated with a form.
For example, after a person leaves a comment, I post a confirmation message and then give them the ability to "Return to Article" or "Go to Home Page" as seen in Post #27 above.
Is there a way to implement you awesome solution with these non-form-based, standalone buttons?? :-/
(Since you created the sprite from my original buttons, there really isn't any way to tell whether a button uses your sprite-approach or is an image button - except for the hover-over behavior. So, I suppose I could keep using my image buttons in cases like this, however, if I can implement your solution site-wide, that would be the best!)