I'm not looking to get flamed here sooo... I'm just posting this link so people can do a quick peek and begin to understand the difference between amps, receivers, pre-amps, and other items typically related to home audio/video systems (with some bleed-over towards the PC sound spectrum as well):
http://www.crutchfield.com/m_10400/Receivers-Amps-Tuners.html?tp=33
Just the basic descriptions right there on that one page alone should be enough for most people to grasp the concepts of the different pieces of hardware.
Thanks man nice link.