I never took a formal guitar lesson from an instructor, but I did play in a band and researched many of the online offerings. I believe I can offer a few valuable tips about inexpensive guitar lessons that are available cheaply. So for those who are looking for other alternatives from the $40+ an hour that you will pay for a teacher, I can help.
First, ignore any advertisement that says learn guitar fast. Like anything else, if you want to play, it will take time and lots of practice, which iss the main reason I don't recommend paying large dollars for the kids guitar. Most will try it for a short time and then it will gather dust in the garage or closet! You should buy a kids guitar for that you can make playable with a little effort, but you don't have to spend a lot for a guitar.
When I played in the band, I was fortunate that the other players were very experienced. Billy had picked up a guitar when he was five years old and never looked back. He plays almost entirely by ear, with an occasional look at a Youtube video. He couldn't explain what he was doing, but he sure played well. The drummer took formal lessons from the time he was a child, could play anything from a sheet of music, but was a little uncomfortable with improvisation. Playing with these two was an experience that illustrated the pros and cons of each approach!
There are two products that I highly recommend. The first is authored by Steve Krenz and is named "Learn and Master Guitar," and the last I looked, it was funded by Gibson Guitars. The second method is taught by David Reed, and his approach is called "Improvise for Real."
"Learn, and Master Guitar" consists of a set of instructional videos, jam tracks and a manual, that classically teaches you. It is a course that has benefitted many guitarists and is very popular. If you take the course, you learn to read music and learn all the techniques that an advanced guitarist requires. They have a great forum which is very popular, and Steve himself would chime in answer some of the more difficult questions. It is an excellent course if you favor a strict learning regimen. I have used it, and it is a great course! Be prepared to spend about two years to master the material he presents. I never had the discipline to get through it, but many do!
The second offering is one that suits my personality. The "Improvise for Real" course by David Reed. He presents the method that has been used by those who play by ear, and he has formalized how they learn to play so well. He teaches almost no formalized music theory, but yet he gives you the gift of understanding your instrument and insights into what music theory is. No intervals, circle of fifths, caged method, or oddball scales, he bases all his theory on the numbers 1-7 where each is a note of the major scale. He insists that you just explore and listen to the notes on your instrument and he presents a set of exercises that accomplish a mastery that is very intuitive. The course begins with a 300-page book that explains his method. This is the place to start. After reading a bit, the next step is to visit his website and purchase the jam tracks that make it guitar lessons fun. He has sets of inexpensive jam tracks which are structured in different keys and modes, and you improvise over them. This method works for me. For those who want a sample of his instruction, he has free Youtube videos available. His course is applicable to any instrument, not just for those buying it for guitar lessons!
Each course is about a 15O dollars in total. The "Learn and Master Guitar" course costs that for all the materials, and the "Improvise for Real" starts at only $30. You then add materials as required. Search the Internet for their websites, you will find more information and might pay a little less!
Each course provides excellent guitar lessons. I have bought and paid for both, and one of them will suit your style. Enjoy!