Use PayPal, E-Gold, or many of the other online payment methods.
You need to weigh your risk vs reward on this type of site carefully. Currently there are very few ways (actually none that many people would consider sending you money through) to receive payments anonymously, which is what you are looking for.
Your best shot is cash sent to a private PO Box. Or have them send it to your neighbors house and check their mail before they get home

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I doubt there would be many purchasers though.
To make money in this field you have to take some risk. I would also not want to take credit cards as fraud is high in these types of transactions.