You can also send report to the scammer's embassy in your country, your embassy in scammer's country...
But honestly, I personally doubt the effectiveness of such reports.
The scammers choose chat rooms and dating sites because the person in love offers the chance of the biggest payoffs.
The scammers start by stealing a photo from an internet site.
They prefer to use images of white people capitalising on stereotypes and perceptions.
The Nigerian dating scams target the lonely and vulnerable.
The most common comment of victims who think they have found the love of their life is "I can't believe I was so stupid!
Though this list mostly specializes on Russian scams, they also list Nigerian female scammers.