The textbook for Biology 19 for Fall 09 is:
Life: The Science of Biology, Eighth Edition 2008
Auth: Sadava, Heller, Orians, Purves, Hillis,
For information on ordering:
If you are enrolling only in Bio19 and not planning to take Bio18, you can purchase just Volume I of this book (chapters 1-20), at lower cost.
The publishers also have an option for subscribing to the textbook s an “ebook”, available at the above website, this is much cheaper than purchasing a hard copy. However, it does mean you no longer have access to the book after the class ends (which may be a consideration if you might want to use it in the future as a reference for standardized test preparation or other biology classes) and it will cost you extra to print out any of the pages.