amazon.com, search with "magnetic paper towl holder", one of the link is as follows,
http://www.amazon.com/exec/obidos/tg/detail/-/B0000X8X2Y/qid=1092110439/sr=-1/ref=sr__1_etk-kitchen/102-3995641-2594542?v=glance&s=kitchen&n=284507

i remember that buyers can pickup their amazon order from local target, not sure if this is
still the current policy, though. just in case you may want to save a few bucks on shipping.