Version 1.2.0 of my sound file editing program, ADPCM, is available on my web page:
http://www.silogic.com/trains/ADPCM.html
This version lets you
1. play the clips in a sound file
2. copy a clip from one sound file to another
3. insert your own created clip into a sound file
4. edit the sound file clip index
With (3), you can insert any 4 bit IMA ADPCM clip into a PS2 or PS3 sound file and you can insert any 24 bit big endian signed PCM clip into a PS3 sound file. You can create those types of clips using freely available tools (I used Audacity and Sox - links to these on my web page).