UPDATE: The main search functions are back! FreeDB search will be offline until sometime tomorrow.
Our search server finally gave up the ghost and its dead. We’re bringing up a back-up server to take over for it, but it will take another 8 hours for the indexes to be complete.
Sorry for the inconvenience!
In the meantime, you can donate some money!
UPDATE: by Dave at 1730 UTC
Until about 1715 UTC the search server was only available to the master site – this is now fixed. Sorry for the additional inconvenience, and thanks for bearing with us.
Previously Dave said:
The server server seems to be a little sick again today – the load average was over 100 just now. As a result I’m trying to reboot the server now, and I’ve put request rate-limiting in place on the main server, so you may find that various things aren’t working at the moment. 😦
Watch this space for updates.
MetaBrainz Blog 
So how much does a new server cost?
A server for something like this will likely run about $3000.