Last week I bought the O'Brien Classic Guitar Building course for $107. Best $107 I've spent in a long long time. I've watched and downloaded the entire 25+ hours of videos. I don't know if I ever will build a classic guitar, but most of the building and finishing techniques also apply to steel string guitars. It takes 25 hours for the course because O'Brien shows almost all the steps in real time. All except the glue drying time.
I'm a relative novice at guitar building. I'm starting my eighth guitar now and I've built a bunch of banjos. O'Brien's instructions have added a new layer of logic and continuity to my thinking about guitar building.
I especially liked the french polishing section. I recently decided that french polishing was my finishing method of choice for guitars. I've FP'd two guitars so far. I've watched at least 10 online videos on FP and averaged them out to come up with my own technique. Parts of my technique worked pretty good and parts not so good. Since watching O'Brien's videos, I now understand why my methods worked or didn't work so well.

So, my recommendation is to buy the course before the price goes up to the regular price of $167. Robbie is not my cousin and I am not getting any payment for this recommendation.

And when he finishes the steel string course, I want to be first in line to buy it.
Dan