e2guardian is available in the "Universe" repository of Ubuntu 17.04 "Zesty Zapus" and better. It's also available in Debian 9.0 "Stretch" and better.
These Linux versions are still in prerelease state. If you're running an older version of Ubuntu or Debian, it's best to backport the package. Maybe we can help you; post here for help. Or you can upgrade your entire PC to a prerelease version of Ubuntu or Debian, but this is not recommended.