If you want free sheet music for modern pieces, you won't find'm. There's copyrights involved, you know? On the other hand, you can look for midi files and collections of them; you might find some folk's interpretations of various songs out there. You could always print out the notation and chording. That's about as close as you'll get, legally.
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Kawai GS-40 grand with midi-out, Yamaha PSR synths