Andrew,

If you are an established business with satisfied customers, then ask them to refer your company to their fellow business owners or associates. Offer a 10% discount on the next month's service fee if their lead becomes a customer.

Also try networking with office managers, procurement managers, who ever is the person who is responsible for researching and/or hiring outside vendors. The big boss usually is not the one doing the initial vetting. Even if they do not make the final decision, usually their recommendations hold the most weight with the decision maker.