Kelly L. Stone's "Time to Write" (Adams Media 2008) features advice from over 100 professional writers, interwoven by her own commentary on finding time to write.
Introduced in chapter 2 and reiterated throughout the text she focuses on what she aptly calls the "Burning Desire to Write", which is something that writers just know they have to do, and as such, are deeply motivated and will find the time to write.
She also says paramount to writing success is devising a schedule and sticking to it no matter what. And in chapter 4, she sketches out seven types of schedules for different lifestyles, also pointing out the pros and cons of each.
The rest of the book gives tips and advice on planning, making goals, and overcoming resistance to writing. The appendices feature a character sheet, online resources, writers organizations and short biographies and web pages of all the interviewed writers.
I found that the book is abundant with helpful, practical and sound advice and definately worth the time.