See this site:
http://www.wired.com/news/culture/0,1284,53818,00.html
See this page for a news story about the Nigerian scam:
http://news.bbc.co.uk/hi/english/world/africa/newsid_1944000/1944801.stm
This page at the US Secret Service has information:
http://www.secretservice.gov/alert419.shtml
See this site also:
"The Internet Fraud Complaint Center (IFCC) is a partnership between the Federal Bureau of Investigation (FBI) and the National White Collar Crime Center (NW3C)."http://www1.ifccfbi.gov/index.asp
If using rules and filters with your ISP and e-mail shell program still let them through, do what I do. I forward all messages of this type that get through my e-mail program filters and my ISP anti-spam filtersto the FTC in the hopes that by reporting them, they will eventually be stopped. While there have been some arrests in this scam, there are still some people perpetuating it that haven't been arrested and stopped. In regards to those that are being scammed by this, as technology support personnel, I feel obligated to educate as many non-techies as possible to spread the word and keep others safe from this type of abuse. Our children are the best ones to educate with this since they're so tech savvy!
Best wishes.