Abbie Mood, Early interventionist & Freelance Writer
I would look and post on Craigslist as well as search local papers. You might also want to try to partner with a preschool or public school and see if they will allow you to offer your services there. I second Emily's advice, as well, in creating business cards and getting recommendations. You might also want to create postcards/flyers and post them at Starbucks, family centers, and anywhere else that someone with young children might see them!