You may think that getting a booth at a local event is something that only venders and large companies should do. Actually, local events create great networking and marketing opportunities for any business.
Consider the cost/benefit analysis. You need a table, a chair, some promotional material (which you probably already have on hand), maybe have an employee staff the booth, and some refreshments for the employee.
Assuming the event is 4 hours long, you may have to pay the employee something like $50. The booth space itself is going to vary, but most small events will give you an "information only" booth for around $100 or less. Maybe you spring for some new promotional material to the tune of $300. Total cost: around $500.
Now some adjustments to our cost total: Any undistributed promotional material can be used another day. Anything that was distributed was obviously worth the trip. Your real cost, over and above what you would have spent anyways, is more like $150. Now the only question is, how much business will your company's appearance generate?
If the day's efforts result in a single new customer, for most businesses, that's certainly worth $150. You have to consider how much business a new customer will do over the life of the account, not just the initial purchase. Maybe you'll generate renewed interest from a past customer. Maybe you'll meet a new, valuable contact. In any case you'll increase awareness of your business, which helps make all of your other marketing efforts more effective.
You're also generating goodwill. Most small events benefit a local charity or non-profit in some way or another. Your support will be appreciated by the organizers as well as many attendees.
The next time your Chamber of Commerce, Downtown Events Organization, PTA or other organ ization puts on an event where you can expect 500 or more people in attendance, consider taking advantage of the opportunity. You can even split the cost by going in on a table or booth with a network partner, or two, or three.