No you didn't brick your phone, you need to follow the I9000 guide in the stickied threads. You need to load a Captivate kernel before fully rebooting your phone.
First off get your phone back into download mode. Pull battery and usb cable, restart Odin, then follow this method to get you into download mode, put in battery, hold down both volume buttons, keep holding them and plug in the USB cable.
First when you flash a I9000 rom make sure you uncheck autoreboot on Odin.
When this done when you flash the Rom it will say Restet in Odin. At that time pull your battery and USB cable.
Restart Odin and load the Captivate kernel. Put you battery in, hold both volume buttons, keep them held and plug in the USB cable, should go into download mode. Start Odin, and it should be fine to let it autoreboot.
I missed something it will be in the stickied thread.
Sent from my SAMSUNG-SGH-I897 using XDA App
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