Xcode 3 is still a free download from http://connect.apple.com/ http://connect.apple.com/ also on the Xcode 4 page it has a link in the bottom right that allows

Xcode 3 is still a free download from http://connect.apple.com/ http://connect.apple.com/ also on the Xcode 4 page it has a link in the bottom right that allows you go to the Xcode 3 download page.