Newbie to Home Automation, Newbie Question on X10, Please Help

[curtiplas <Curtis.LaPrise@xxxxxxxxx>]

So I looked through the last four pages or so and didn't see a post
related to my question so here it goes, hopefully I don't get too much
flac for asking this.

I want to start implementing x10 devices through out my home.  I have
a server that is being used as a personal web server but can
definitely handle more, so I was planning on running the automation
software off of that (probably something like MisterHouse or something
else that also offers a web interface).  I understand (atleast I think
I do) that the X10 devices send and recieve their signals through the
power lines, but heres my real question how do I "link" them with my
computer so that my software can control them.  Also I'm probably
assuming this is way to simple but here is my assumption of how x10
works I hardwire the device or plug and play depending such as a new
light fixture or electrical outlet, I then hardwire some device into
the power lines, I'm assuming this device would have a USB interface
(or serial but I don't have any serial ports).  Please help me clear
this all up and also tell me what this device is called so that I can
use my computer to control the devices, or point me in a better
direction (cheaper) than X10.