The Game Audio Tutorial

You might also be looking our old book : "The Game Audio Tutorial", or new book : Game Audio Implementation.

Unreal 3 Audio engine

These videos from creative labs look at the implementation of audio in the Unreal 3 engine.
The UT2004 was pretty weak in terms of sound in it's basic incarnation (although many developer extended this significantly for their own games) so I'm looking forward to seeing what they've come up with.
Links have a habit of changing / disappearing. I have done my best to make sure these are correct but do not take any responsibility for what might be at the end of them ! Please let me know if any are not working and I will do my best to update them.