Just boot into recovery, plug in your usb cable to your phone and computer, and flash a stock image using Odin. I would suggest you go ahead and flash a rooted stock image using these instructions.
http://xdaforums.com/showthread.php?t=1739426
If you want straight stock:
http://xdaforums.com/showthread.php?t=1737848
Odin can be found here:
http://xdaforums.com/showthread.php?t=1722686
These are all stickied at the top of Android Development Thread. In the future, please search first.
I flashed to stock and it is still in boot loop. it can go to download mode still but no recovery and still bootloop. Please help.
I'm having the same problem. I followed the no-counter-tripping method to flash a root-injected stock ROM and it worked fine.
I flashed to CM9 and the camera wasn't working, so I used Odin to flash back to the same root-injected stock ROM and now it never finishes booting.
I noticed that flashing to the root-injected ROM didn't delete my apps, which seems strange. I suspect that there's something lingering from CM9 that is causing the loop in stock. I don't know any way to wipe the device and flash only the root-injected ROM, but I'm hoping that will fix it. Is there a way?