Ideally you would buy the CDs to help support the projects. If you are in a hurry or want to try them out first then you can grab them from your closest mirror listed on their sites. Www.netbsd.org, freebsd.org, openbsd.org .
They can all do net installs off boot floppy/cdrom or you can download and install from local sources. Check the websites for more info on installs for your hardware. More.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.