Wanna Play Detective?

I need a techie type person to help with a case I'm working on. I've got an e-mail that was sent from a postmaster.co.uk address and I think I may have some info that would help track it down, or at least narrow down to an ISP. If you need more, I can probably get more with a court order. This would just be helping me figure out where to go with this, you wouldn't ever actually be subpoenaed to testify or anything, but I could definitely use some assistance on this. We can e-mail more about it today if you can help. Thanks!!