Is there any AirPort product that supports to receive audio streaming and share a hard drive on USB? My impression is that I need both an Airport Express for sound, and an AirPort Extreme for sharing the hard drive.&#1;

Is this true, or there are alternatives?
Your impression is correct. AirPort Express's USB port does not support hard drives, and AirPort Extreme doesn't have an audio output jack:



Sucks, don't it?