Hi there,
I'm just starting to dig in to silverstripe, so i'm not entirely sure if this is a question about themes ... but i think it is.

I would like to be able to create and manage items so that i can create playlists and such. Think of it like this - i would like to have an inventory interface that looks somewhat similar to something like itunes or spotify ... where you have your entire library, then "playlists" and favorites and such.

Does anyone know if there is a theme out there that will do this?

Thanks!

Theme will only contain basic HTML / CSS. You'll also need to create Models to represent your data in the database. I recommend you do the tutorials first (esp tutorial 5) since this will most of the concepts you'll need in building your application.