I would like a program that will batch watermark/stamp my files with an audio file I provide at a chosen time interval and/or repetition.

The idea is that if I then have 40 wav files I'm about to convert to mp3's and put online, I can quickly spread a not-too-annoying clip saying where they came from through them in one batch process.

Do you guys know of any such program? How do others go about doing this?

edit: Clarification - I am not looking for digital rights management - just a automated program that will drop a .wav clip overtop of my songs saying where they came from.

Thanks.