If you don't have a Library created with music like I didn't, you can open up music files directly from the File Picker by clicking Open or Play Something, which is pretty cumbersome though:



So gently caress that, I needed to add some to the Library. To do that, clicked on "Tell me More".

...which then opens up a Metro IE10 browsing session telling you how...except it wants to be opened up in the desktop version of IE10.



So I oblige, click the button and open it up in the desktop. You get the exact same page, but at least you can follow the instructions now as it's directing you to perform desktop actions, just like Win7 with adding your folder to the Library.