If you've got the dough, and you are a straight male, I would recommend taking a cab to either Long Beach(the 2nd street area, belmont shore), Hollywood, or Huntington Beach. My personal preference would be huntington, you can pretty much count on finding lots of hot girls. Long Beach would be the closest to the pan ams but it can be hit or miss, especially if you dont know your way around the city. Hollywood is fun, I like the dive bars not the clubs.
Again if you dont want to gamble with your one night out in So cal I would recommend Huntington Beach (Main st.). Its got about 10 bars all in about 3 blocks everyone of them stocked with hot chicks, no dress codes, a few with dance floors. When your done partying all the cabs are right there, and if your empty handed at 12:30 go over to Perk's for some cougar hunting.