Scheduled Downtime
On Friday 21 April 2023 @ 5pm MT, this website will be down for maintenance and expected to return online the morning of 24 April 2023 at the latest

NetCDF installation links not available in WRF compiling tutorial

I think it should work to download these directly from the GitHub repositories for the libraries:

You'll just need to scroll down to find the particular version you're looking for.