This feels surreal. I just googled If I Wrote a Book About You and discovered that you can preorder it at any one of a number of places! It will be available on Amazon.com, Amazon.ca, Amazon.co.uk, Chapters, Powells (my beloved Powells!), and Barnes & Noble. It will even be available at Walmart's site.
In my googling, I also discovered that the first result for "If I wrote a book about you" links to the lyrics of one of Beyonce's songs. She sings, "If I wrote a book about where we stand, the title of my book would be 'Life with Superman.'" Clearly, she needs a copy of If I Wrote a Book About You for baby Blue Ivy. Maybe we could make a special gold-plated one.