On Writing: A Memoir Of The Craft
The "career" book I recommend most frequently... not just to aspiring writers.
On Writing: A Memoir of the Craft by Stephen King (New York, Scribner / Simon & Shuster 2000)
Why you should read it: Not to become a horror fiction writer but to answer this career question for yourself: if money was no object, where would you obsessively focus your work energy and time?