Get him Korg DS-10. It's a video game for the Nintendo DS, but it's a synthesizer/sequencer. Compared to something like Launchpad + Ableton Live, it's actually more accesible for a kid (despite the "bank of dials" effect). Check this video for what's possible with it:

https://www.youtube.com/watch?v=TXTyMxM5vuY

That's one of my favorite chiptune artists, Anthony Seeha, tearing it up on two Nintendo DSes (running two copies of Korg DS-10).

As for resources, honestly, just show him DS-10 videos on YouTube. That's the modern music lesson. Kids everywhere are learning guitar, piano and Ableton Live from Internet tutorials and hard work.

And dude, you're awesome. I wish my dad had gotten me something like that when I was eight. Well, I mean, not instead of the years of piano lessons he actually got me... :)