I've used several different programs, Pro Tools, Cakewalk, and n-Track... I have to say that in my experiences, n-Track has been the easiest to use. The free version has unlimited tracks, but you can only add effects to the first 2 tracks. I think the mixdown is limited, but it doesn't give you any sound drop outs or beeps like some other free software.
-Gabriel-
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"Keep away from me; I'm not your enemy... I've got all I need; my social lunacy..."