I bought it from Monoprice.com and it worked for me..
3523 Car Charger (Cigarette Lighter) to USB Female Converter - Black $1.16
7448 USB 2.0 A Male to Micro 5pin Male 28/26AWG Cable - 3ft1 $1.12
Subtotal : $2.28
Shipping & Handling Cost : $1.73
GRAND TOTAL : $4.01
NOTE: I had to spend 30 seconds with a knife to shave a squared end of the USB cable to a angled end so it fits perfectly in the (Captivate) Galaxy S.
3523 Car Charger (Cigarette Lighter) to USB Female Converter - Black $1.16
7448 USB 2.0 A Male to Micro 5pin Male 28/26AWG Cable - 3ft1 $1.12
Subtotal : $2.28
Shipping & Handling Cost : $1.73
GRAND TOTAL : $4.01
NOTE: I had to spend 30 seconds with a knife to shave a squared end of the USB cable to a angled end so it fits perfectly in the (Captivate) Galaxy S.