how to implement an iTunes type site

I've been charged with creating an iTunes type capability. Ideally, we would like to have people submit a credit card when they register and have that card charged every time they watch a video. One of the main purposes of this site is for re-certification, and we'd like the users to be able to download and print-out their history. I'd set up an iTunes tore but I need to control branding.

FWIW, I know Joomla well and have started working with Drupal.

Anything modules or 3rd party services spring to mind?