The slow death of the electric guitarThe convention couldn’t sound less rock-and-roll — the National Association of Music Merchants Show. But when the doors open at the Anaheim Convention Center, people stream in to scour rows of Fenders, Les Pauls and the oddball, custom-built creations such as the 5-foot-4-inch mermaid guitar crafted of 15 kinds of wood. Standing in the center of the biggest, six-string candy store in the United St
