I have been acquainted with Dillon Smith for the past four years in my capacity as faculty advisor to the Spanish Club at Anytown High School. Dillon has shown himself to be a leader, serving as club president as a senior, and as treasurer during his junior year.
Not to worry, though, because you could have a few alternatives: colleagues, clients, and former supervisors. In this case, it's not about who you know, but what they -- your referees -- know about your performance.
Many states regulate what an employer may say about a former employee—for example, when giving a reference to a prospective employer. Does your state make employers immune from liability for statements they make in a reference?
If your former supervisor is still working with the company, she may provide a "professional" reference. Such a reference gives only very basic information about former employees because of concerns that a company could be sued for defamation.
I have given two school-based referees, as they can speak with knowledge of my teaching skills and overall contribution to their schools. However, should you also wish to contact my agency employer, the address is: The Rip-Off Agency, 123 Hill Street, Bristol BS3 4RT.