I need to find a piece of free (or reasonably priced) clip art of
praying hands superimposed over a world globe. I need something really
classy looking for a book cover. Can you help???

You couldn't do better than Albrecht Dürer's praying hands:
http://bilder.snooweatinganima.de/duerer_praying_hands.JPG

There are many other sites with them on Google Images.

Then you can pick the globe of your choice there.  I would go with one
of the photos from space.

And then find someone who can super impose them.

someone else will have to advise you copywrite and price.  Dürer's
hands should be in the public domain, and an pic of the globe should
be too.