In case you can't use the sqlcrack program (I believe you must be sysadmin to run this software) you may need to think about another method.  Do you have access to either EM or QA where via a sysadmin id where the password was saved?  If so you could create yourself an id and change the sa password.

If there really is nothing, you may need to think about reinstalling.  using the latest backups of  the user databases and the msdb database.   This is a fair bit a work, so you may not want to do this without eliminating all other options.