Most any software has the capabilitiesof doing what you want. What you don't have are the capabilities of doing is delivering a competent performance with competent engineering skills to create a national sounding commercial. This can be accomplished with a Shure SM58 with an additional foam pop filter. A simple audio interface such as the Digidesign M-Box 2 that will include ProTools for under $500 plus microphone. That's all you need.

Then you need to know the directions to Carnegie hall.

I know the directions
Ms. Remy Ann David

Just take a left

Well, main problem here is that your question is too vague. First off, like Remy already hinted, the software is not going to make a huge difference. Sure, there are plenty of plugins and modules for modifying the voice - pitch correction, various effects like compressors, reverb and what not - but we need to know exactly what you're trying to do here.

What, precisely, is it you don't like about your voice? For that matter what kind of vocals? Singing, speech? Is it the actual way your voice sounds you don't like, or are you having problems with the actual performance (i.e. out of tune and similar issues)?

I get the impression that you're talking about the former (but I'm guessing here, more details needed, if you're having problems with the performance you just need to take Remy's advice about Carnegie Hall :-) ), which is a bit harder to do anything about. You can apply various effects, but it's unlikely to solve the problem. If your performance is not good, no amount of software or hardware is going to fix it. A good singer and sound engineer can produce high quality recording with very basic equipment (the SM58 is one of my favorite mics by the way, with the right pre-amp it's nothing short of magic!).

Best way is to improve your singing technique (or speech technique if this is about voice-overs or similar). You can quite radically improve the way your voice sounds by learning proper technique, and I'm speaking from personal experience here. Taking singing lessons has improved my voice quite dramatically in less than a year. So, if you're not doing it already, sign yourself up for some singing lessons. Don't expect miracles over-night - learning how to sing properly takes time - but you should be experiencing quite a lot of improvement in within 6 months or so (else you might want to look for a different teacher :-) )

Hope this helps,
MetalGod

Well, first, thanks for all of your answers! My voice is not that bad but sometimes it sounds not really good, especially on high notes. (some pitch problems), I want to know if there's anything I can do with that? (I mean, with a software)...

Everybody wants a metal box to do the work.............

Ref to MetalGod's post. Learn singing technique. Much cheaper than a metal box and it lasts a lot longer.

What I can tell you about your voice:

Sometimes I find that popular music, composers & performers frequently try to perform material outside of their vocal capabilities. I.e. not the right voice for the part. In the wrong key, etc..

When it comes to vocalizing:

Too many people try to sing with only available air in their lungs. Never taking a good solid full breath, through the nose when possible, before letting loose.

One of the worst voice wrecker's out there is not utilizing proper support. It's all but crap when people tell you to support from the diaphragm. The diaphragm is not a muscle. You must support from your abdominal muscles, all the way down to your ass. In fact it should feel like you have to take a crap but are holding back. That's proper support. And that will get you more into the range when you have that support. Provided that you're not unrealistic about your vocal range.

Men & women generally have voices within 3 usable ranges. If you are a guy trying to seem like Frankie Valli? You might want to consider sex change surgery first? If you are a woman and are trying to sound like Joe Cocker? You might want to consider a quart of Jack Daniels & a carton of Chesterfield's?

But proper breathing & support along with good posture is your first starting point.

If you're interested in studying voice with an old-time Metropolitan Opera star, drop me a line?

Listening to voice lessons and recording voices for over 52 years
Ms. Remy Ann David

Things like EQ, reverb, compression, and of course the use of high quality microphones/preamps/converters will enhance your vocal takes. But they will not make you sound like a more skilled singer.

If you absolutely have to fake it, try Melodyne. Very flexible. Very easy to use. Not the most transparent software, but probably the most powerful. If you overdo it, it will be noticable. Be prepared to do dozens of takes and pick even the individual syllables that work best. You'll spend hours doing it, and if you're anything like me, you won't enjoy it.

Also, you will not have the satisfaction of actually being that good. So like the others have said, just learn to sing better.

As I've said before (though, I'm no pro), the magic is in the tracking.

Since I've started recording my own vocals I've had to make DRASTIC changes to my technique to get it to sound as I want. Did I say drastic?
And FWIW, I sing live every weekend so I just chalk it up as a slice of humble pie and a learning experience.

When John Lennon was on the old Dick Cavett show, Dick was telling John a story about the new young artist who asked the engineers to use a filter that would remove the speaker's southern drawl.

Dick Cavett started to explain to John that there was no such thing, at which point John one-upped him by stating, "You don't have to explain it to me, I'm in the business, you know."

Like duh! John Lennon was in the recording business!
Still, there is no such filter.

Hey Remy,

right on track with the info. My vocal coach used to tell me to use my "bathroom muscles".

For 0coldzero, its humble pie time. The tape doesn't lie, but friends do or they don't know the difference. Have you seen American Idol?

Best thing to do is learn your tendencies and I'll give you several that I've discovered most singers have problems with. (this comes from teaching voice, singing and choirs for the past 17 years and singing for the last 30.

1. PITCH - make all intervals smaller on descending lines, especially half steps
2. INTERVALS- know them - don't just guess - if its a major 3rd sing a major 3rd - if you don't know what that means - learn theory (lots available for free online) - truly know the difference in whole and half steps in your voice, not just on paper. If you think you can do this try to do it with random series of 4-5 half/whole step phrases in varying order. You may learn quite a bit.
3. PHRASES - don't relax at the end of phrases - keep air and support continuing through the line until you breath in
4. SUPPORT - use air wisely (here's where a coach can help) a great tone can be created by using the amount of air you can blow through a thin straw. Too much ain't a good thing. This is where Remy's advice is spot on
5. VOWELS Know what vowel is coming out of your mouth at all times and when you're changing vowels. Singing is sustained pitch on vowel sounds and sometimes on voiced consonants in pop music. Extreme changes in vowels is the equivalent of changing instruments in the middle of a phrase. Ya don't see too many instrumentalist doin' that.

Thanks for your support guys! But I have one last question, when I ''import'' a song into CakeWalk Sonar, it sounds pretty weird, I mean, the quality is very very bad, but anywhere else (cool edit pro, windows media player) it sounds right....what should I do with that?

I don't know where I can change the bit rate in this software