I am trying to write a little application that will play back wavs / mp3s. I'd like to have independent control over both the pitch and the speed which they are played back at. For example, I'd like to be able to play something say 75% speed without altering the pitch, or play something a half-step higher without changing the speed. Nearly any combination of pitch/speed changes. I have been searching around for something that will do it, but I haven't found anything definitive yet. Will FMod do what I want? TIA

Yup. The FMod Documentation is the best you'll find. I haven't played around with the speed/pitch at all, but it's in there somewhere.