Trade shows often have keynote speakers and breakout sessions. You can check with TSNN.com to find out where trade shows are going to be and what the topic of the trade show will be as far ahead as two years. When you complete out your profile, they will even give you the contact information for the event coordinator.
Ask what their fee range or budget is for speakers, suggesting you’ll work within their budget. There have been several times when I’ve been offered more than my average fee because I’ve left it up to the organizer.
It is a great idea to mail introduction information to the attendees. You can either provide the information to the event coordinator or ask that you can send the information directly. In which case, you’ll be able to increase your database by doing the mailing yourself. When they do the mailing however, the benefit is that it will be a promotion from a source the participants already trust.
There is never an event too small. I spoke at an association function in Palo Alto for no fee and a year later they asked if I would speak at their annual function and made $3,500 for an hour long keynote. Many of the local events will have statewide or national events that have allocated a budget for keynotes.