Federal customs officials have stopped more than 20,000 pairs of counterfeit luxury shoes from tip-toeing into the U.S. from China.  U.S. Customs and Border Protection says four shipments of fake Christian Louboutin shoes were seized on Tuesday at the Los Angeles-Long Beach seaport complex, and another shipment was seized July 27.  Spokesman Jaime Ruiz says the shoes have a value of $57,490, but could have sold on the U.S. market for $18million. The vaunted French designer’s shoes come in an array of colors and styles, often commanding thousands of dollars per pair from well-heeled customers.  Countless A-list celebrities regularly wear Christian Louboutin, which are famed for their distinctive red lacquered soles. They typically sell for upwards of $800, and can exceed will into four figures. The knock-off shoes were likely destined for swap meets or sale through websites.  Typically buyers are unaware that counterfeit items are fake, and often believe that they are buying an original product at a significant discount.  In the 2011 fiscal year, there were 1,020 trade seizures with a domestic value exceeding $37million at Los Angeles/Long Beach seaport complex alone.  This represents an 18per cent increase in the number of seizures from fiscal year 2010.  Ruiz says the shoes in this case were very good counterfeits and will likely be destroyed. Mail Online