Following the links and a bit of googling will get you a lot of the old source code.
Keep in mind quoting myself:
Also, compiling them at times will drive you nuts, they rely on a bunch of old packages that are no longer around. I actually had to download gigs and gigs of old linux CDs & DVDs to get what I needed and their dependencies.
If you want to / have to compile it do not try to make it work with newer versions of stuff. Go out download all the old Ubuntu DVDs with all the software and dependencies and install it in a VM and compile it there. The time it will take to hunt down every old package and then trying to get them to work on a 2021 OS will not be worth it. There are copies pre 2010 Ubuntu and other linux distros out there will all the needed packages. Trust me on this. Not saying it can't be done, but it's a lot harder.
-Dave