i dont know about free, but yo check out pr1mesounds
you have to pay for mb of samples, but they got a ton of shit, from percussion, flutes, wind samples mad shit
Get on of your friends with a triton, motif, asr10 and have them hit chords and sample them into PC/MAC and chop them up and use them on your MPC? I do this often..
If you get in touch I might be able to zip a few up and shoot them accross....
They are really nice pro Acustic samples.... tell me what you want.... Violins.... Cello.... Bass... etc... I cannot send you a heap.... but you could pitch shift them and do what you will....