2G Touch firmware rollback help

Does anyone know where I can get the pre-4.0 firmware for the iPod Touch? I upgraded to 4.0 and the battery life is horrible since doing so and the only benefit is a unified mailbox and folders. I'd rather have the battery life back.

On a side note, it seems that the battery life is only horrible when the wifi is turned on whether it's sleeping or not. I turned off the usual suspects as well in testing.

Thanks for any help.