I've never tried singing or screaming, bit I'd like to now.
Can anyone tell me where I can find a free download program with some kind of death metal vox?

I don't think you're going to find a program for altering just vocals. There is probably a method of turning vocals into death metal growls but you should be able to find it if it exists with a Google search.

Yeah, that's what I've been doing, but everything I downloaded is garbage. I've got an awful voice, and the only thing these cheap programs are doing is making it worse.

I've always thought of death metal vocals as being a more human/natural thing. If you want the vocals to sound good, you're going to have to do it naturally first then go back add a little reverb and echo and be done.

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Lots of bands use a myriad of effects with their vocals. And again, many dont.

Do you have a guitar amp? do you have a mic? can you plug said mic into said guitar amp?
Maybe throw some pedals in between, bass overdrives jsut add a bit of grit, while retaining the low end. Regular overdrives work as well, but will take out some low end. You can also use distortion pedals, but they will change your vocals more than any overdrive, more or less changing your voice into something completely different, instead of just adding grit to your voice.

Another fun tool to use is an octaver. you can get soem evil sounding effects if you run your vocal track with a regular track, and a slightly quieter track one or two octaves down. Behemoth used this on Demigod.

Satyr from Satyricon uses a pretty epic midi controller for his vocals. I've seen them in concert a few times, and he had a bigger midi controller than both of the guitarists combined. He used it for distortion, chorus, some eq effects, echos, and stereo echos where it sounded like his voice was circling the venue. It was awesome.

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