This is the free beginner version of Finale Notation Software. It is allows you to make simple scores. It does not include all of the options that are in Finale PrintMusic or the professional version of Finale. This may be a good thing, though, because it allows you to begin composing music quickly without having to learn all of the details of the program.
Professional level music notation software - one of the only FREE notation software applications designed for professional use.
Create, print, and share sheet music online. You can find also find popular songs for strings that were arranged by other users.
http://audacity.sourceforge.net/
Audacity is free audio and recording software. Musicians can use this to record and listen to their performances.