what sort of stuff are you into...ca has it all
my top list would be:
san francisco - all the clubs are in northbeach, but there's al the touristy stuff to do during the day
highway 1 - this can be real fun if you have a nice car. it goes practicly the whole cost, but you can catch it in monterey and then jump back to 101S around Big Sur I think. You can drive it all the way to LA, but it will take you about 2-3 hours longer. San Simeon is a good camping spot along the coast if you you're interested.
in LA, man, there's so much. spoiledman has the good ones. manhatten beach is also nice. I think you can get discount passes to Six Flags at BK if you want to go there.
in vegas, just stick to the strip, but you can probably get cheaper rooms on freemont along with a big arse light show. RAH is pretty good as is Rain at the top of the palms. I'd avoid hoover dam unless you like sitting in traffic for about two hours.