these are good and cheap http://www.inmotionproducts.com/productDesc.asp?session_id=8cf1bc817c325700444f762d7ca19f38&text_product_id=CM
@slowstephen started
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
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these are good and cheap
http://www.inmotionproducts.com/productDesc.asp?session_id=8cf1bc817c325700444f762d7ca19f38&text_product_id=CM