I will make a comment on MP3 and all kinds of file-sharing and copying, for that matter.
I can't see absolutely any reason why they should be deemed immoral.
Let's say one really enjoys Coca-Cola. One day he decides to make his own drink. So he buys the products, sets up the necessary machines, mixes them up, and produces a homemade Coke; he then drinks it.
No-one would ever say he did something immoral. He certainly did not steal anything at all from the Coca-Cola Company.
Now, another example closer to file-sharing. The same individual thinks the Mona Lisa by D'avinci a very beautiful painting. So he buys a screen, a brush and paints, with which he paints a precise copy of the artwork, which he proceeds to hang on his wall. Has he stolen the painting? Certainly not, as it is still there in the Louvre.
Now, suppose this man lacks the skill to make a good copy of the Mona Lisa. So, instead of painting it himself, he programs a machine to do it, with all the precision of modern technology.
Again, no theft has taken place. It doesn't matter whether the painting is centuries-old or just done; in either case, the artist or those who hold the rights to the painting have absolutely no claims of property over the man's copy of the painting, which he produced out of materials he himself owned.
The same holds for MP3s. No-one is stealing anything. The individual who gets one is making a copy for himself, with materials he owns (in this case, the computer).
Suppose one gets many songs from file-sharing and burns his own CD, which he listens in his house or car. Some will say that he is listening to a stolen product. But if it is stolen, who was it stolen from? The answer will be either recording company, artist or whoever holds the rights to the songs, or perhaps a combination of them.
Well, when something is stolen and has not been destroyed, it is only right to give it back to its rightful owner. But if the man in question gives his CD "back" to one of the parties above, what is the final situation? The party that got this CD was not restituted of anything they lost; instead, they have more than they have ever produced; the recording company has got one extra CD they never made or bought.
It is true, they payed for the recording; but the recording was not stolen when this CD was burnt; rather, a copy of it was made. And to make a copy is not at all like stealing.
In the Middle Ages, it was the freedom with which people copied works from one another (or from older sources) that guaranteed we would have such a large collection of works from before the invention of the printing press.
What is indeed wrong is to take credit for what was not made by ourselves, or to profit from the distribution of said ideas (these profits are rightly the property of the recording company, but not a copy which it didn't make). But to make a copy in no way violates anyone's property rights.
"But what if you were a musician? Would you like people to get your songs for free?" This question is, strictly speaking, irrelevant, but if people really want an answer, here it is:
Nowadays I think I would have no problem with it. My main objective when writing or composing would be to reach many people, and file-sharing is a step in that direction. However, once I got into the business, and my livelihood depended on the people's purchasing my material from the official distributors, my mind may change. Still, even though I would prefer to receive money, would I be justified in claiming that those who copied my work (or who copied copies of my work) were stealing? Not at all.
Last, there are some who will argue thus: "file-sharing is against the law. Therefore, it is immoral to do it." I do not attempt to answer this argument by now, but only to make a question to those who defend this line of thinking: if the only reason why this is immoral is because the law forbids it, should the law have forbidden it in the first place?