Looks like the server hosting the website is down.
I'm not familiar with crosstool-ng, but have you had a look in the repos of whatever distro you are running? If there is a crosstool-ng package available, you might be better off installing that as it should work with your installed system.
If you can't find a suitable package in the repos of your linux distro, you'll have to download the latest version of the source from github and build/install it from there!
