brianlu, Welcome to the forum!
Tell us what youtube vids you are looking at and exactly what you want to do. The tutorial will start here and be authored by all the volunteers that frequent the forum.
Most of us use the x-10 CM15a and the included Active Home Pro software as a stepping off point to computer home automation. From there, you can pick up on some great 3rd party software written by the members that allow you to do things such as : voice control, I-phone/I-touch control, webpage control and the like. There is a whole thread that can be found on 3rd party add-ons.
Tell us what you want to do, and someone will be able to point you in the right direction
PS- no need to post twice, we'll all get the message