How do I reclaim my URL

[Battaglia]

Ok my friend had his site hosted with a company and sorted his .com with them also. Recently it seems they've vanished of the face of the planet though, no site no office no nothing

So he comes to me and asked if I'd host his site which isnt a prob, the prob is he wants to use his .com but its under control of this company who we have no contact with.

Soooooooooooo my question is what is the way of going about regaining control of his .com

Cheers