I recently picked up a copy of "Uncle John's Certified Organic Bathroom Reader" and one chapter (pages 176-180 called The Frog in the Mineshaft) talks about the need to be aware of what is happening to frogs around the world and what it means when they become threatened. In general, this is a very readable book for anyone who wants interesting, funny, facts on perhaps being a little "green", but any book or article that mentions the biodiversity and natural value of frogs deserves a mention. Check it out if you get the chance.