For the last few months I've been using a couple of Perl specific Google Co-op searches.
The Perl search pulls results from 72 assorted Perl related sites including CPAN and perldoc.perl.org. It tends to work for those questions that you're not even sure where to ask.
Perhaps more useful is the CPAN search which I find often outperforms search.cpan.org. In particular it finds 'one word' module names like CGI or FCGI both of which search.cpan.org currently overlooks.
If you have any suggestions for sites I've missed or other improvements give me a shout.