Google is a marvellous thing
Here are lots of cleft lip dog photos. Seems more common in brachycephalic breeds, though this isn't a strict rule.
Boxer - adult and pup, looks like same dog:
http://upload.wikimedia.org/wikipedi..._adult_dog.JPG
File:Cleft lip in boxer.JPG - Wikimedia Commons
File:Cleft lip in boxer 2.JPG - Wikimedia Commons
Bulldog, pup:
http://images.onesite.com/pawsconnec...pics/gussi.jpg
Looks like pit bull type/similar, pup:
http://www.virginmedia.com/images/do...es-431x300.jpg
Bullmastiff, slightly older pup:
http://www.spencermanbullies.com/sit...g.w300h225.jpg
American Cocker Spaniel, pup, before and after surgery:
http://www.zimfamilycockers.com/Angel-BeforeSurgery.jpg
http://www.zimfamilycockers.com/Angel-AfterSurgery.jpg
Pit bull/Rottie mix, baby whelp:
dog.jpg (image)
Staffie, adult:
Duo, the Two-Nosed Dog. - Neatorama
Chihuahua/rat terrier mix - actually just a cleft nose, lip cleft barely visible, adult:
http://neatorama.cachefly.net/images...o-nose-dog.jpg
Mongrel, very severe cleft lip, jaw, nose, adult:
http://data5.blog.de/media/155/2939155_18054fa357_m.jpg
Interesting stuff. Most of these were on the first 2 pages of the google search for "dog cleft lip".