PCB Design

Hi, I'm looking for a PCB to be designed for a product. The product plays MP3 files stored internally, and updated via USB and is powered by a dynamo that the user turns. The Power from the dynamo needs to be stored in some capacitors so that first the device is charged, then the charge is used to play an mp3 that is about 1-2 minutes long.

I have a more detailed specification if you're interested.
in summary, design PCB to:
take power from dynamo,
store power,
play mp3 through 2-3W amp.

Thanks
Matt.