You'd think that setting up a pair of loudspeakers would be a piece of cake: Stick 'em where they look good, and be done with it. It can be as simple as that, but to get the best sound from your speakers, you'll have to do a bit more work.
Because speakers interact with the room in which they are placed—you know, sounds bounce off of walls and floors and get sucked up by furniture and stuff—paying attention to the placement of your speakers within that room can make a big difference in sound quality. With your speakers optimally positioned, your system will sound better. And, in my experience, better sound leads to discovering more music.
And more music leads to more fun...
So, where should we begin? John Atkinson has made speaker setup a bit easier with his essay, "Getting the Best from Your Loudspeakers." JA takes the time to go over some of the basics—things even the most experienced audiophiles should keep in mind—and he does it in a way that makes setup interesting and fun. (Not insignificant!) To follow along, you'll need JA's Editor's Choice Sampler & Test CD, a suite of signals that'll guide you on your way.
And in addition to JA's essay, you'll find several other articles related to loudspeakers and speaker placement, so you can learn even more.