From what I can tell, this is a great free program:
Ardour v2.4.1
http://ardour.org/downloadDon't know if it can do what you want, but it seems like very powerful free software.
A great resource is Computer Music magazine. You can go to your nearest Border's bookstore and read it in-store for free. It always has several mentions of free music software for all platforms. If you have the $15 to buy it, it comes with a DVD that has music production software on it. If you have a laptop, you can preview that software in the store before you buy it [the DVD is not bagged at all]. It seriously comes with a full production suite including VST's, editors, hosts, etc. that are full versions [comes with demos also]. Keep in mind you get what you pay for, but if you are looking for a cheap and quick way into techno prod., this is it.
And if you find that you are _really_ serious about making music you will eventually want some kind of midi/keyboard interface. Most come with some sort of software. I prefer Cubase LE as bundled software.
Check here for an assortment of info and programs:
http://www.hitsquad.com/smm/Happy hunting and let me know how it turns out!
_theJestre