Haiku Baby is written and illustrated by Betsy Snyder (Random House, 2008). WINNER 2009 - Beginning with Books "Best Books for Babies" list.
I love this board book for babies/toddlers and have brought it for both my nephews. Adhering to the 17 syllable format, it may not contain the kind of haiku I would write, but they are fun for kids and do what haiku do best - celebrate Nature. Each page has a theme: rain, flower, sun, leaf, snow, moon, with an animal, and is tabbed to make it easier for little fingers to turn the pages.
Kiwis - you can get it from Fishpond here. It's also available from Amazon where you can look inside and see the illustrations and simple poems for yourself - Amazon US and Amazon UK. You can also take an animated sneak-peak here.