Nexus 7 owners needing otg cable here is one for 83 cents with free shipping.
Amazon.com: SANOXY Micro USB Host Mode OTG Cable Flash Drive SD T-Flash Card Adapter FOR Samsung GT-i9100 i9100 Galaxy S II 2 GT-N7000 Galaxy Note: Cell Phones & Accessories
Amazon.com: SANOXY Micro USB Host Mode OTG Cable Flash Drive SD T-Flash Card Adapter FOR Samsung GT-i9100 i9100 Galaxy S II 2 GT-N7000 Galaxy Note: Cell Phones & Accessories