It was very easy to assemble. The only compliant I had was they combined the build instructions with the Blinky Grid. Not a big deal, but it did confuse my eight year old son for awhile. For early beginners this could be enough of a problem to cause a fright.
I purchased my kit from Maker Shed, but they do sell them directly from their website. All of their projects are Open Hardware, so you can build on their ideas.
Here is a link to the programming page. http://www.wayneandlayne.com/blinky_programmer/