i wrote this in a different thread but it might be helpful:
sorta off topic but I'd like to recommend to anyone who doesn't know about it yet: this integration of Melodyne into X3 is stunningly cool. especially if you spring for the editor upgrade. record an audio file, say a bassline

, then Without even needing to load Melodyne, drag the audio file to a MIDI track and presto audio to midi conversion!! yes the midi track might need some clean up, but how long have we been waiting for audio to midi that works this well and this simply?!
in fact if you take the extra time to load the audio file into melodyne before audio/midi conversion and clean up the timing and length and especially pitch correct the notes (polyphonically in Editor upgrade) you get a near perfect midi file WITH the feel that you played the original. it doesn't just convert to notes it also translates the velocity of the notes
so even if i play kinda bad ( which is the case when playing fast) i can get a perfectly timed audio file without time stretching artifacts etc
anyway...not trying to do a commercial here. just thought i would mention it