Stock Firmware GPL Code
From DD-WRT Wiki
Introduction
This page contains links to the GPL code of stock firmwares for easy finding. There's a high chance of the links going stale so don't be surprised if they don't work.
Links
http://www.filehosting.org/file/details/228172/e1500_v1.0.00.009_us.tar.gz
http://www.filehosting.org/file/details/228175/e2500_v1.0.00_12.tar.gz
http://www.filehosting.org/file/details/228178/E3200_1.0.00.013_us.tar.gz