Great suggestion man! I will check that out!What would a book bring you ? Isn't the interest of a specific blues rendering in the detail of the interpretation, never captured in written form ? You have to listen to your favorite players, and emulate their playing. Slow blues has the advantage of being ... slow. It is usually easier to follow than fast tunes. Check someone like S. Turrentine (eg "Scrap Iron" on Duke Pearson's "The Right Touch").