UPDATE: Thanks to my current partnerships I'm now able to access various games on Steam as I need them. This document is now (mostly) obsolete, unless you just want to give me keys for no reason at all.
This is my internal hit list for researching XAudio2, to aid in developing FAudio.
When working on large amounts of games in an unofficial capacity, it can be difficult finding which games even have XAudio2 in the first place, let alone use a feature set that we can take apart and implement. Generally you have to Google the game with variants of "xaudio2" and pray that a support ticket comes up (most of the time, nothing comes up), though occasionally you get lucky and it shows up in a database like this.
Even then, once you have a list, you have to figure out how to work with your budget - sure, it's a tax writeoff, but to spend money you usually need to... er, have money. The tradition up to now was to use a small Steam Wallet alon