Bumping this up because I was finally able to get hold of this- http://www.amazon.co.jp/gp/product/4048542192/ref=ox_ya_oh_product
It's a memorial book with covers most of Osaka's career. It's split up basically into illustrations (things like promo art, DVD covers, etc) and more industry based internal sketches. You really get to see what variety he had, you could barely tell any two series came from the same pencil. It only helps underline the fact that the industry lost a huge talent.
The art itself is a joy to drool over. There's lavish stuff here for the likes of G Gundam, Escaflowne, Cowboy Bebop and more. I was suprised to discover he'd actually drawn the G Gundam DVD covers I'd questioned as out of character in the past (shows what I know, eh?). There's even an awesome set of pages which show a ton of step by step storyboarRAB he did for one of the Bebop fight scenes...wow. Further to that, some aborted G Gundam character design sketches I've never seen anywhere else.
My only real complaint is that there are artworks shown in the wrap around cover that don't actually feature in the book But if you enjoyed the man's work, I'd heartily suggest picking this up.