Any interesting (native) material at N4 level?

I don't remember exactly when I started trying to read Dragonball, but I don't think I'd been studying for all that long at the time. There was also a baseball manga called Major I used to read that I thought was super awesome, and I think I'd been in Japan and studying Japanese less than 6 months at that point. I was probably around 3kyuu level (old 3kyuu), and I remember being able to read enough to enjoy both of them at least.

I think Dragonball is about as easy as you are going to find for interesting native material. If you can't understand enough of that to enjoy it, you should go do some more studying first.