I've found two great quotes about writing in this month's Oxford American and I thought I'd share:
From Lolis Eric Elie's contributor bio: "Lacking any lucrative talents, I write for a living."
And from Rick Bragg's essay, Upending The Muse: "You write because you have to and you do not whine about it, because as hard as writing is it is not real work, life roofing, or toting cement blocks, or wiping tables at a Waffle House. But you treat it like real work."
And of course, there's the quote I've used as my email signature since I don't know when:
“I’m a writer. Never did an honest day’s work in my life. Drink, anyone?” -- Andy Serwer