SELECt id, payer_emailFROM paypal_ipn_ordersWHERe payer_email IN ( SELECt payer_email FROM paypal_ipn_orders GROUP BY payer_email HAVINg COUNT(id) > 1)
sqlfiddle

SELECt id, payer_emailFROM paypal_ipn_ordersWHERe payer_email IN ( SELECt payer_email FROM paypal_ipn_orders GROUP BY payer_email HAVINg COUNT(id) > 1)
sqlfiddle