I can't access it either. It looks like it is either a DNS issue (domain router cannot be found) or the Lemon server has crashed and needs to be rebooted. Lemon64 is also down which leads me to believe it is a server issue.

The Lemon server, as already mentioned above, is quite unstable at times. Possibly it gets overloaded sometimes by some of the scripts being run if too many visitors are accessing the site at once. That can sometimes happen to the main classicamiga.com site server too.