I know nothing about art. That said, my wife has a drawing that she wants to use for a business card. How do I convert the image to vector or another easily scalable graphic? I scanned it in, but it is basically a bitmap...

if its well defined enough you could try illustrator CS2's livetrace feature. Its saved me a lot of time quite a few times.

If you don't have access to Illustrator (since it is quite expensive), you can also use Inkscape (which is free) which has an equivalent feature. The results mightn't be as good (I haven't used tracing enough to make a valid comparison) but if the image is simple enough you can give it a go.