Are you using IPIVR or CVP? for your queues?
It is important to remember that IPCC never actually handles the calls the calls are held and processed by the peripherals eg the IVR (CVP or IPIVR) and Call Manager.
I'll focus on IPIVR now. In this case the wav files are held in a directory on the server before being uploaded to the repository to be played back.
You can record a file in a number of ways.
1. Record on any PC. The format is ulaw 8bit mono. Sound Recorder can provide this format.
Then take this file and upload it to the server prior to uploading it to the repositiry and including it in an aef. I ususally use this method to create the static files required for most messages.
2. Create an aef that records and saves the wavs directly on the server. I use this method to record the dynamic messages in call centres allowing users to easily change messages on the fly.