Your first mistake was believing the answers you seeked were in the Acme:: namespace. Acme is for jokes, just look at Acme::BooK::Is::My::Bitch.

However even if you had searched all of CPAN you would be sadly disappointed to find that there are no modules that currently do this. The problem is that for computers pattern recognition is very difficult. I don't know where to start on solving this problem, but if you could get the base audio wave and sufficently filter out any extraneous noise you would probably want to use PDL to do the necessary analysis to separate out the dits and dahs. From there the decoding is simple.

Another option, if you are a HAM who has recently gotten onto General or Extra bandplan since the morse restriction was lifted is to acutally learn Morse. It doesn't take too long to pick up if you use the Koch method (about 2 weeks) and you'll find the experience much more enjoyable.

Signal analysis is a topic that takes up entire university courses, which is why commercial Morse decoders are sold and are the price they are.