Add MP3 Files To Native Music Player? I use Linux on the desktop and have zero access to iTunes. I'm in a position where I have to use an iPhone for a while. 

I can plug my phone to my computer and mount the storage drive. Where would I dip my MP3 collection in order to pay them in the native application? 

It's an iPhone 4S updated to the latest version of iOS.
afaik since iOS 5 there is no longer a Linux Application that supports syncing Music to an iPhone (there used to be GTKpod)

The easiest would be to install WINE and then iTunes I suppose.