Contacts mate, get friendly with the door staff in your area, chat to them, get to know them, ask if there's any work going in other local areas (dont work in the place you go out in), and behave in a professional manner even when out socializing and when chatting to these guys.
Fair enough, if you're out, have a couple of drinks, but be polite, well dressed, well mannered and well spoken, you will then give them an idea of your general attitude and when you ask for contacts, they will give you a blinding result (maybe even telling you to mention they sent you).
You must ALWAYS be professional, even when not on the job, its amazing how far the networks spread, and this network is near as damn it all about word of mouth.
Good luck and good hunting!