Learn to torrent. :-)
Torrenting works like this:
A torrent is basically single file, like a big .zip or .rar file. It's a file that contains multiple pieces of the file/files that you want to download. The .torrent file is what allows the sharing and transferring from person 2 person (P2P).
However a torrenting program (that is, a program that you torrent with)...is NOT in the same genre and class as what are usually referred to a P2P Programs (such as Limewire, Frostwire, Kazaa, Bearshare, WinMX, Morpheus, Napster, etc.) A torrenting program does not have the ability to search for torrent files, the way you would in Limewire.
Instead, you search the internet, say for example, at google "Metallica discography torrent" and then download the torrent file from whatever site you choose that has it with the torrenting program.
The program that you torrent with is specifically designed (and pretty much only designed) to download and upload.
When you open up a torrent of multiple files in a torrenting program, you will be prompted to check/uncheck files you do and do not wish to download. You don't have to download everything in a torrent file in order to download the torrent successfully. Let's say you only want 1 Metallica album, uncheck the others, but leave the album you want to download checked. The program and torrent will only download that album out of the whole discography, and when that one album is downloaded the torrent as a whole will have been "fully downloaded" as a status of 100% complete. It does this, because out of that torrent, it finished downloading 100% of what you wanted it to.
Use a torrenting program called uTorrent
Some search engines for torrenting are:
www.piratebay.org
www.isohunt.com
Alternatively, you can google for torrents as well.
Happy torrent hunting. :-D