Ok, I know, this may take all the anonymity out of the internet and so on, but being the playchild I am, I actually made a file with my very own personal accent, using my headset and Windows Media recorder only.
It's a bit quiet so you may have to adjust volume to hear it, but in times of YouTube and free video hosting I was surprised I couldn't find anything to upload an audio file to and have it streamed.
Anyway, enjoy...