I disagree (though not particularly strongly) with the comments claiming that you should learn classical mechanics first. You don't need much physics background to learn to do basic calculations with wave functions, and to pick up ideas like observables-as-differential-operators. If you want a list of good web resources and textbooks together with good organizing commentary, I recommend looking at Gerardus 't Hooft's page: Theoretical physics as a challenge. You can safely ignore the paragraphs in the beginning about his page being only for people who want to win the Nobel prize in physics.

I disagree (though not particularly strongly) with the comments claiming that you should learn classical mechanics first. You don't need much physics background to learn to do basic calculations with wave functions, and to pick up ideas like observables-as-differential-operators. If you want a list of good web resources and textbooks together with good organizing commentary, I recommend looking at Gerardus 't Hooft's page: Theoretical physics as a challenge. You can safely ignore the paragraphs in the beginning about his page being only for people who want to win the Nobel prize in physics.