Confused Stormtrooper.

[A Black Falcon]

Well obviously there will always be some evil people who want to join the badguys. All of the officers, and technical crew are such people. The grunts, however, are the ones who would need to be clones. When it comes to doing evil, immoral, dangerous work they'd have to be clones. And there voices are almost, so far as I can tell, all the same. And they have numbers instead of names or ranks. Furthermore, when Luke walks into Leia's cell in ANH, she reacts "aren't you a little short for a stormtrooper?", suggesting that they're all the same height.

No. Not at all. First. Remember, the Empire didn't take over the Republic. It replaced the Republic from inside. Imperial officers graduate from the same training schools and academies as Republic officers before them. Same for Imperial troops... except the Empire does much better brainwashing. But it's easy to get recruits once you control the galaxy! They needed clones because they weren't expecting a war and didn't have the time to train an army. The Empire is built on war and has the time to set up training and recruitment facilities. They use propaganda and news to get people to join up and defend their government. Many people would listen -- it IS the legal government after all! And it's not like they hear about the bad things... propaganda is called propaganda for a reason, and media control is a given in such a government (as best they can anyway). So no. Your premise is flawed. Okay, some stormtroopers are clones, I'll admit that. But most to all? Absolutely not. The Empire has more than enough resources to recruit them and train them to mindlessly follow orders, and they would. And it's a lot quicker than growing clones -- that takes years!

Numbers instead of names? True. Once you become a Stormtrooper one of their main goals is consuming your individuality. To do this you've got the all-covering suits, the numbers instead of names, the intensive training, etc... but it certainly does not indicate that they are clones. As for height, it's the same on every army in the world -- you have height restrictions. Minimum, probably maximum too, best averages... they would go after people of the "right" height so Stormtroopers can fit into a minimum of uniform sizes, I'd assume.

As for the voices, that's just part of the personality destruction, I think. Radios and speaking units that make them sound less like individuals. But they don't all sound the same, regardless.