I'm having the same problem!
I don't think it's relative to the iPhone, though. iTunes was working just fine for me, as far as burning CDs and things goes, until a few weeks ago, which is when I moved into my dorm at school. since then, I've been getting the "disc burner not found" message, and I really don't understand why. I do have an iPod Touch, but I hadn't been having this problem previously. help!