Is there some easy way to get cpan to tell me what modules are available?

Use cpanp -m regex

$ cpanp -m App::Ack
   1 App::Ack                       1.96     PETDANCE
   2 App::Ack::Plugin                        PETDANCE
   3 App::Ack::Plugin::Basic                 PETDANCE
   4 App::Ack::Repository                    PETDANCE
   5 App::Ack::Repository::Basic             PETDANCE
   6 App::Ack::Resource                      PETDANCE
   7 App::Ack::Resource::Basic               PETDANCE
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Or, start cpan, and type h, to get interactive help, but remember, cpan -m is not the same as cpan> m

cpan[1]> m /App::Ack/
  Database was generated on Thu, 24 May 2012 20:07:03 GMT
Module  = App::Ack               (PETDANCE/ack-1.96.tar.gz)
Module  = App::Ack::Plugin       (PETDANCE/ack-1.96.tar.gz)
Module  = App::Ack::Plugin::Basic (PETDANCE/ack-1.96.tar.gz)
Module  = App::Ack::Repository   (PETDANCE/ack-1.96.tar.gz)
Module  < App::Ack::Repository::Basic (PETDANCE/ack-1.96.tar.gz)
Module  = App::Ack::Resource     (PETDANCE/ack-1.96.tar.gz)
Module  < App::Ack::Resource::Basic (PETDANCE/ack-1.96.tar.gz)
7 items found
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