Finally, after two rounds of international auto shows in Frankfurt and Tokyo, it's time for the 2009 L.A. Auto Show. It's the first big American show of the season and it's already shaping up nicely thanks to a few notable world debuts that have already been announced.The 2010 Porsche Boxster Spyder got the ball rolling when it appeared in early November. A high-performance version of the standard Boxster, the Spyder adds horsepower while doing away with the standard model's convertible roof.For those looking for something a little more mainstream, the 2011 Buick Regal will make its first auto show appearance in Los Angeles. A smaller, more performance-oriented sedan, the new Regal is hoping to once again reshape Buick's image. If that's still not enough practicality for you, the 2010 Toyota Sienna minivan is making its world debut in L.A. as well. It's one of the few true minivans left and Toyota is determined to keep it around for some time to come.Our coverage starts on December 2 when we'll have photos, blog posts and videos from the show floor.