Lua and Python are probably still the more popular scripting languages. That said, at this point, it’s not really so much the specific language (Lua, Java, etc.) so much as it’d be scripting/programming concepts. A local community college course in programming can work great for that, regardless of what language they focus on. Once you understand the basic concepts, it’s pretty easy to apply that knowledge to whatever scripting language you may run across.
It also hugely depends on what kind of game you’re working on. If you’re doing a game with FMOD, WWise, etc, then you may not need to do any kind of scripting at all. If you’re doing a Flash-based game, then you might find yourself wanting to do a little “ActionScript” to implement some cool interactive audio features.
Btw, here’s an interesting article by very smart man, Chris Hecker. In the comments section people discuss various scripting languages..
Glad you enjoyed GameSoundCon! It was a blast this year 🙂