Free sheet music in the public domain:
http://imslp.org/wiki/Keyboard_Sonata_in_F_minor,_K.466_(Scarlatti,_Domenico)
Free MP3 of this recording:
https://drive.google.com/file/d/0Bzwr-5tDUtSEMkZOcEhILTZIbkk/view?usp=sharing
Recorded with 2 CharterOak E700 microphones and Apogee Duet:
http://www.apogeedigital.com/products/duet