Bartender Cocktails

What is a book you can use to learn more about wine?
I am a waiter in New York City with good cocktail knowledge and a little wine knowledge, but I have to learn more about wine, specifically the regions. Can anyone recommend a concise book on this subject? Thanks!
Wine for Dummies. It was the textbook in my university course: Geography of Wine. It must be cheap and that is clear and to the point.
Juggling Bartenders – Japan Probe