ScanScore - ScanScore is a sheet music scanning software.
Sibelius - Sibelius is a virtual score creation tool which allows composers to easily create new piano scores, developed by Avid.
SmartScore - Scan, edit and transpose your music in just minutes.
MuseScore.org - Create, play back and print beautiful sheet music with free and easy to use music notation software MuseScore. For Windows, Mac and Linux.
NEURATRON PhotoScore - Music scanning & PDF to notation software.
Finale - Finale, the world standard for music notation software, lets you compose, arrange, notate, and print engraver-quality sheet music.