You can trace it back pretty close to the scammer, at least all the way the registered owner of the originating IP address. I just went through something like this last week, and yes, the scammers were in Nigeria. Read the post and find out how to trace it back. Just look at the properties of the email message you got and look for the orinating IP address, in Outlook or Outlook Express, it's preceeded by "Received from:"
Anyway, the last post in this thread, tells you about how to trace it back.
http://www.clubcobra.com/forums/show...threadid=53150