Where can I download older versions of Blender? I was trying to re-download the original Blender 2.8, however it goes directly to the 2.81 download page instead.

How can I access downloads for previous versions of Blender and installers for older releases?
Accordoing to the blender.org fortunately "Your old files are safe, every Blender release is available for download. Forever." Just go to the download site and look for previous versions at the bottom of the page.

2.79:
https://www.blender.org/download/previous-versions/

2.80:
https://download.blender.org/release/Blender2.80/

Every build:
https://download.blender.org/release/