http://www.goldwave.com
View post (computer based multi-track recorder)
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I use a program called Goldwave to layer tracks like that. It's shareware (30 days I think) and it's easy to use. Basically you record the different tracks, copy - then mix into the final track. You may have to play with it a little but it's not too hard to figure out. I definitely recommend it.
http://www.goldwave.com
http://www.goldwave.com