Third Street Promenade is always fun, good food, shopping, and a short walk to the beach... (it's not an s&m site, although they really should have rethought that url)
http://www.downtownsm.com/
And if you're more tourist oriented, you may want to do that Hollywood thing...
http://www.classicmovies.org/links/hollywoodtourism.htm
Whatever you do, have a wonderful time. LA is the place to be!
