Want an e-book version of the nation’s bestselling nonfiction hardcovers? Don’t bother looking on the iBookstore. Apple still hasn’t struck a deal with Random House, publisher of George W. Bush’s Decision Points and Laura Hillenbrand’s Unbroken.

For now, iPad users who want to get any of Random House’s bestsellers -- which also include John Grisham’s The Confession and Stieg Larsson’s The Girl with the Dragon Tattoo -- need to visit Apple’s App Store and download the free application for the Kindle or the Nook.

On those e-bookstores, consumers are snapping up the Random House titles that they can’t get on the iBookstore. The bestsellers: Stieg Larsson’s The Girl with the Dragon Tattoo and John Grisham’s The Confession (on the Nook) and Confession and Unbroken (on the Kindle). On the iBookstore, by contrast, the top two titles are Tom Clancy’s Dead or Alive and Justin Helpern’s Sh*t My Dad Says. (There is no centralized e-book bestsellers list.)

Publishers declined to speak to PW for attribution about their e-book sales, but the Kindle Store appears to be the most popular e-book retailer, followed distantly by Barnes & Noble's Nook storefront and then by the iBookstore. Digital book sales, as quickly as they're rising, also still remain a small percent of publishers’ total revenues.

Apple offers more than 130,000 books in its iBookstore and more than 300,000 applications in its App Store. The store does not break out how many of the 300,000 apps are for books.

Apple still keeps its iBookstore titles and its book apps separate. The iBookstore only exists on mobile devices (such as iPads and iPhones) whereas the App Store is also available on computers. (The iBookstore is contained within iBooks, a book-reader app.)

Apple just added more than 100 illustrated e-books to its iBookstore. On Dec. 15, Simon & Schuster Children’s Publishing announced that it was offering e-book versions of 17 of its titles, including Ian Falconer’s Olivia picture book series and Justin Richardson and Peter Parnell’s And Tango Makes Three.

And yesterday Open Road Integrated Media, a digital content company that publishes and markets e-books, announced that it is offering nine illustrated stories -- including Callie Cat and Christmas Kitten -- on Apple’s iBookstore. (This week Open Road also started to sell e-books of the first 19 of the 150 titles in Albert Whitman’s The Boxcar Children Mysteries series.)

Not everyone is embracing the iBookstore, though. At this time Oceanhouse Media -- the leading publisher of children's digital book apps on Apple’s App Store, with the exclusive right to make apps of Dr. Seuss’s work -- is not planning to sell there. “We believe that in order to have an effective digital children’s book you need a level of interactivity that cannot be provided for with iBooks,” says Oceanhouse Media president Michel Kripalani. “Only apps can deliver this high level of interactivity, and much of the work is custom to each specific title.”

Oceanhouse Media has sold more than half a million Dr. Seuss digital book apps since its first release (How the Grinch Stole Christmas!) just one year ago, says Kripalani. With 140 apps on the app store, it sells “many thousands” of apps per day, he says.

One reason: they’re inexpensive compared to iBooks. “Personally, I believe that many of the books on the iBookstore are overpriced,” says Kripalani. “Why spend $14 on a static digital book when you can have a fully interactive Dr. Seuss, Berenstain Bears, or Mercer Mayer book for $1.99 to $3.99?”

Apple lets publishers set prices but requires them to split revenues 70-30. That means that on a $10 e-book or app sale, Apple gets $3 and the publishers and authors split the remaining $7. The author, then, typically gets 25% of that $7, or $1.25.

It’s time-consuming to produce e-books of old titles. Publishers need to establish a royalty addendum to many contracts, and then they need to create the digital versions of the stories.