I have recently downloaded this software called CwGet and played with it a little. It seems to work fairly well and is easy to use. Be sure to read the review of this software from Break In magagzine which has a link at the bottom of the webpage.
Also try this webpage from the NorCal QRP group:http://www.fix.net/~jparker/norcal/cwdecod/decoder.htm
One of their members wrote a decoder program that is free.
I haven't personally tried this one yet though.