These fantastic wooden puzzles designed by Oguro Sabu of U-Plan are now available at Chigo. You can find dozens of wooden puzzles designed by Oguro on the U-Plan website; he also designed several pieces for Naef (info via daddytypes).

If you’re handy in the woodshop, Oguro has several books available at Amazon JP with templates to make your own puzzles.

Unfortunately, the books no longer appear to be available. If anyone knows another source, let me know!