I've been playing for 40 years. The things I can play I play very well, but most of it is still pretty basic stuff and I'm restricted to rock and blues styles and some basic country. In many ways, technique-wise I'm at an advanced level, but there's so much more I need to learn in order to get really good.
I play in a band and I want to be able to use stuff I learn in the band setting. I probably need some theory and I'm more than willing to learn, but I want to be able to apply it, not just memorize a bunch of shit I'll never use, yet I would also like to build a better foundation. I am most interested in learning jazz and country styles, so I really would like to begin with some theory that I can start incorporating right away into the band.
So any advice on a specific approach?
Books or DVDs? Online or private lessons?