Attend Meetups related to the content of your event
When it's your turn to speak start by saying: "You know I am working on this event..."
Put stickers with your event logo on your badge
Make sure you attend related Facebook Groups events
Open Bluetooth at conferences and change the name of your device to something like "Great event coming up"
Attend Linkedin Groups related events
Create your own Meetup on the topic and start collecting attendees
Search Eventful/Upcoming list of events and look for related events to attend
Make sure you have a brochure/flyer/invite with you at all times
Make your vcard and keep it ready at all times
Attend related Bar Camps and make connections
Use LinkedIN Q&A to arrange meetings
Carry a presentation about the event with you and be prepared to pass it on
Sponsor smaller events – Meetups – Bar Camps – User Generated Events
Send an email every week to people in your area with the events that are about to happen.
Yahoo! can send you a lot of very qualified traffic. Take advantage of it.
Create your own Meet Up group or join other groups. Sometimes, if your event is really interesting, administrators of other groups will be happy to pass the word to their members.
Join groups and use their forums to let people know about your event.
Don't be afraid to contact local newspapers and other publications to let them know about your event. In most cases, they will find this information useful and relevant, and they'll be happy to share it with their readers