I just bought a basic Hori case. It works well.
I own 3 games for the system and would recommend them all, sorta.
Zelda: OoT 3DS - It's OoT. A great game and a great port.
SSF4 3DS - a really good version of SSF4. Controls take some getting used to, but the entire game is in there. It's actually really impressive. All the characters, moves, combos (that I can see), modes, etc. Don't bother if you're not a fan.
Ghost Recon Shadow Wars - a really deep, involving, and enjoyable turn-based strategy game. It looks a bit rough (I think it was originally meant for the DS), but there's a ton here.