The thing you can "buy" is private lessons, in-person, with someone who not only understands how they do what they do but can also express it to you in a way that you understand. That interaction is what's missing from all the other approaches. Yes, it's expensive, and so is a guitar, so is housing, so is a car... so you have to ask yourself whether you want this bad enough to pay for it.
I agree and I disagree with OU812 :-) You CAN be taught many things about "how to improvise" but the teacher CAN'T move your fingers for you, CAN'T internalize the ideas for you. As a music major with a jazz degree, I took MANY classes in which teachers of all instruments would impart not just the notes that made up a scale, or which chords that scale would work for, or ways to use that scale in different styles, but the more difficult-to-summarize concept of "musicianship" and what makes playing "musical" and how to "think like a jazz player" (or whatever other style intrigues you.) It took many years and thousands of hours of practice alone, playing in ensemble situations, going to jam sessions, sweating bullets at gigs, and just plain keeping at it to get to the point where these ideas began to show up in my playing. I'm still working at that... it is a lifetime pursuit, despite my having reached a professional level of skill on my instrument years ago, and I'm sure many other musicians will back this statement.
So, here's the actionable advice you are looking for:
- take lessons
- stop playing the licks you know and start learning new ones. one way to do this is to try inverting the patterns you do know: play the licks and scale patterns backwards. This is especially useful for breaking out of pentatonic prison... so many players learn their pentatonics only from the root up... try playing from the top note down, and then from each note in the middle to the next occurrence of that note... BACKWARDS. I.e. don't play your blues scale as 1 b3 4 b5 5 b7. Play downwards 1 b7 5 b5 4 b3 1. Then do the same thing starting on b3. Then on 5. And so on.
- make up new melodies of your own over chords or songs that you know. keep it simple. the idea is to connect your ears, your brain, and your fingers. try to simultaneously sing what you play and play what you sing. This will require you to slow WAY down and that's fine. Fast is not automatically good. Musical, lyrical, melodic, interesting is GOOD.
- when you come up with a short melodic phrase or idea that you like, try to play it in different positions on the neck, and over different chords, and in different songs.
- try running a recorder while you practice. if you stumble on something you like, go back and learn your own licks :-)
Do NOT plan to be great overnight, or in a month, or in a year. This is a long LONG slow journey. At the same time, if you really take this advice to heart and FORCE yourself to stop repeating what you "know" and start making yourself do new things, you will experience breakthroughs and improvements that will surprise you, and you'll find yourself progressing more quickly than you have in the past.
Just take it slow, take it easy, and keep at it. We all go through this. You'll get there.
Good luck!