From a technical perspective it is perfectly possible to trace this individual. The essential information is contained within his IM posts, because the system needs to know where to send replies to. This information alone is not sufficient to locate him, but a competent programmer could use it together with other databases to track him down. It's basically what the authorities do when they suspect somebody of being a terrorist.

What is needed is the political will to do it, and to withstand the voiciferous 'human rights' lobby. I suspect that only when a senior politician's own child gets abducted will anything happen. I have grown very cynical in my old age about large businesses and their political pawns. Too many of them have too much dirty laundry of their own.

I doubt very much that you will get any help at all from Yahoo. What's needed is a high-tech Robin Hood.