I've seen The Art of Racing in the Rain by Garth Stein everywhere—bookstores, racks at Sam's end caps at Target—though it looks like it might be heart-wrenching. Check it out.
From the author's website:
Enzo knows he is different from other dogs: a philosopher with a nearly human soul (and an obsession with opposable thumbs), he has educated himself by watching television extensively, and by listening very closely to the words of his master, Denny Swift, an up-and-coming race car driver. Through Denny, Enzo has gained tremendous insight into the human condition, and he sees that life, like racing, isn't simply about going fast. Using the techniques needed on the race track, one can successfully navigate all of life's ordeals.
On the eve of his death, Enzo takes stock of his life, recalling all that he and his family have been through: the sacrifices Denny has made to succeed professionally; the unexpected loss of Eve, Denny's wife; the three-year battle over their daughter, Zoë, whose maternal grandparents pulled every string to gain custody. In the end, despite what he sees as his own limitations, Enzo comes through heroically to preserve the Swift family, holding in his heart the dream that Denny will become a racing champion with Zoë at his side.
A heart-wrenching but deeply funny and ultimately uplifting story of family, love, loyalty, and hope, The Art of Racing in the Rain is a beautifully crafted and captivating look at the wonders and absurdities of human life...as only a dog could tell it.