Is there an online guitar lesson?

There are online courses for other sites, but they cost money.

I would recommend he start with a beginners book, or watch youtube videos that instruct.

there's an equipboard article about online lessons... does your son read traditional musical notation and play another instrument? is he into doing this or is it more YOUR idea? When I gave lessons I hated the parents of kids who were more interested in the guitar than their children were. No amount of lessons helps a kid who is luke warm on the guitar. I eventualy just banned beginners and only taught only intermediate players! Then I quit because students are a hassle. But anyway...

All stringed instruments are painful at first (your hand is probably not meant to bend in weird directions, depressing pieces of steel, nylon, whatever for long periods of time) and if your kid isn't passionate about working through that you are wasting his time and your money.

the way you phrased this "add playing guitar to his talents" speaks volumes... you have talent or you don't.... you can teach him to develop a talent he has but you can't 'add to his talents' -- if music is not in his blood then let it go and encourage him to pursue something else he is already inclined to excel at... even if you said 'add to his accomplishments' I think playing an instrument is more than an act of dedication and will, there has to be more of a drive than "I can do this," a kid needs to be saying "I am compelled to do this! I have to express myself with a guitar!" My father, an accomplished musician, actively discouraged me from music.... but I was compelled, not by a desire to disobey him, but by a true fascination with music.... that's what your son needs. If that's the case keep talking to us. If its all about looking cool for him and about showing off your kid's talents for you then, at the risk of being offenseive, please just stop now.

Here's Equipboard's take on online lessons. http://equipboard.com/posts/online-guitar-lessons

One thing I would say is that since the internet makes all types of content immediately available, the biggest hurdle to overcome in learning the instrument is personal discipline. Point being, do whatever you need to do to maintain interest and keep practicing. I recommend trying each option you are considering, as many instructors and websites offer free lessons and trials.

Good luck in finding whatever method works best for your son!