Plugin Question: Download Files

Alright. I was not sure if this is in the right forum area, but since it is Plugins and Hacks, I thought I would post this here.

I am actually looking for a plugin that uses some of the functionality of WP e-commerce, but instead of the person being sent the download link for the file they paid for, they would receive a code after paying for their download (mp3). The code would be used to go to a certain page and download the file.

On top of this, the person paying would be documented in a type of client database.

Sounds a little complicated?

Anyway, if anyone has any recommendations on a WordPress plugin that fits close to this, I am all ears. (would like to try to keep it in WordPress before even thinking about either trying an outside program or taking a gander at making something like this.) And yes, if it costs… that is fine with me (as long as it is not the price of nearly an arm and a leg!!!)

Thanks!