Unless it's 2 am (when the bars close) or you're in front of a hotel, that rarely works here.
You (usually) need to call a cab.
This isn't Manhattan, and they don't just drive around for shits and giggles!
If you're in W Hollywood, call Beverly Hills Cab @ (310) 273-6611. Write it on your arm or something. They're super quick. BUT, you need to have an address. Telling them to meet at the corner of x and y usually won't fly. They want an address.
Remember the info you gave them, because they may quiz you when they show up (people will steal your cab). The BH cabs are so awesome they generally check to see if you are whom they're supposed to be picking up.
If for some reason Bev Hills Cab doesn't work, backup is: Yellow Cab... (877) 733-3305.
Anywho... that's my good deed for the day. Write the shit down. Live it; love it; drink it.