any computer store should sell them. if you go to a best buy it would probably cost you more than going to those little corner shops that sell computer parts. Or you can try your luck at Ebay where they are going for about 2.00 US each.
Check Radio Shak, or newegg.com. Shipping will kill u online though. Newegg is awesome for buying computer parts and no they didn't pay me to advertise, i just have had absolutly no problems with them.
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