Originally Posted by: dfaris
Hi, I know nothing of theory but I do want to learn and I will.
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The best place to start is the Guitar Fundamentals 1 & 2 courses (GF1&2). Particularly GF2 because it starts with basic music theory applied directly to the guitar. And then continues on to the relationship between scales and chords.

http://www.guitartricks.com/course.php?input=1
http://www.guitartricks.com/course.php?input=2

Also, here is my brief overview of music theory to give you a large scale road map:

http://www.guitartricks.com/tutorial.php?input=495

Originally Posted by: dfaris
How do you know what scale to use when playing any 3 chords? What makes the root note in that scale, the root?

Great questions. The answers are in these tutorials:

http://www.guitartricks.com/tutorial.php?input=483
http://www.guitartricks.com/tutorial.php?input=491
[QUOTE=dfaris]
Ive been reading on here about theory and find it very fascinating to a point where its an absolute must to learn to be better at guitar.

Music Theory is the set of concepts that describes the nature of musical events. It is the process of mentally identifying the sounds that occur in music. We do this in order to build a consistent set of ideas to describe what happens in music.

Like any endeavor, the more you know about what you doing, then better prepared you are to actually do the activity. Just make sure your theory and practice learning curves keep pace with each other. So that your theoretical knowledge learning curve and your ability to apply those ideas, to practice them and put them to use grow evenly.

Best of success! Let us know how it goes.