I was in the same position in 2006, early retirement, love of guitar, like to build things. Fortunately I found a community college less than an hour drive with a luthiery program! The teacher was Robbie O'Brien (top notch teacher) who now works out of his own shop south of Denver. I should have signed up for Woodworking kindergarden but instead signed up for what amounted to Woodworking graduate school. BEWARE! This can be addictive! All I wanted was a guitar to play but now I am building my 20th.
Robbie offers a one week immersive building class in his shop but 2019 classes are probably full - you can check. And having bought the best six or seven books, I would like to second the recommendation for Courtnall's book.
Chris Conery, luthier