I am not responsible for any legal issues ;P

Step 1: Download and Install a Torrent Client

I don't know which one you want personally I prefer uTorrent

Step 2: Searching for a Torrent

The biggest problem with torrents is that people don't always seed, these people are referred to as leechers.

I usually go to www.thepiratebay.org or www.mininova.org

once you get there pick something you would like to have; software, music, movies, books, "illegal" documents(i.e. The Anarchists Cook Book - yes its technically illegal because you have to put yourself on a registrar upon purchase.), etc

Step 3: Selecting Your Torrent

in the image below we have several options, your best two options are outlined in red.
First off we choose our best options from the title of the torrent, the two I have selected both have detailed titles, one even going so far as to explain how it was made, the other giving the authors name (which is accurate), both give the title of the book and the year it was published.

to narrow down our choice we then look at the seeds, this is highlighted in bright green, and the leechers which is hilighted in blue

The first torrent: The Anarchist Cookbook by William Powell(1971){badluck13_7} has 7 seeds, and 0 leechers. This is okay, but before we select this torrent we will check the next

The second torrent: The Anarchist Cookbook (1971 book scanned) the ORIGINAL book has 43 seeds and 0 leechers, this makes the second torrent your best choice. dclick the torrents title

On this screen you will want to read the comments for any complications with the download

Step 4: Downloading

Click the download link, and it will download the .torrent file which should automatically open with uTorrent, or your chosen application, and begin to download. Congratulations, you just downloaded your first torrent and are on your way to being a pirate. Now Remember seed do not leech