STOCKBRIDGE, MA,.- The Berkshires of Western Massachusetts has become world-renowned for its inspiring landscape and cultural attractions, including such performing arts centers as Tanglewood, Shakespeare & Company, Berkshire Theatre Festival, Jacob’s Pillow, and Barrington Stage Company. Look around the audience of any of these venues this summer, and you might spot Sol Schwartz, a local artist who documents the creative action onstage through his own pencil, pen and brushstroke. A new exhibition looks at the artist’s vibrant, spontaneous drawings, that have captured the beauty and excitement of music, theater and dance for more than a decade; “Sol Schwartz: Drawing in the Dark” is on view at Norman Rockwell Museum from July 9 through October 23, 2011. “It happened by accident,” says Sol Schwartz. “ I used to make little sketches in the corners of my programs when I attended concerts.” Even