Here is a neat program that allows you to plan out your building – it’s called Cube Kingdom and allows you to build “stuff” out of cubes a lot quicker and easier than you could in Minecraft. It’s perfect for planning out what you’d like to build, and has some blocks that are very similar to Minecraft blocks.
This isn’t in Enlish but it’s isn’t too hard to navigator
Download from official web site: http://cubekingdom.web.fc2.com/soft/ck20.zip
For the latest version, always check: http://cubekingdom.web.fc2.com/