Scammed on Craig's List

So, I found a great deal on Craig's List.  A Powerbook G4 1.5 ghz. 310 bucks. Had all the software i would have wanted, and everything. It was perfect. So i email the seller  She says its cool, she is un the uk, and will ship it to me.   

This is where it all went south.  We started the process, and she was going to use TNT shipping and a Western Union payment method. I should have known then something was wrong.  

I followed all my instructions, sent the payment, and alas, all i find out is that from TNT shipping that i got scammed, and the Craigslist/TNT shipper thing is a total scam from the uk. So i am out 300 dollars.  

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