I'm thinking of writing an app to selectively transfer photos/music to and from my iPhone, mostly for fun and personal convenience. However, I'm stuck at the very beginning -- where do I look to find information on how to do this?

Pretty much every link I see talks about developing applications that run on the iPhone, but nothing about desktop app for interfacing with an iPhone.

I'm on Windows (no access to a Mac, but I'll take suggestions for that for when I eventually acquire one), and I'm most familiar with C#, but other languages are definitely an option.

Can anybody offer me a few pointers on getting started? Thanks.