Know-How Exchange : Strategy

I freelance transcribe medical symposia, roundtables, advisory boards, etc for medical communication companies (whose clients are pharmaceutical companies). For years I had a thriving business (mostly word-of-mouth referrals); then the economy happened and some of my clients went out of business or cut back. How can I generate new business? I live in the NYC area and have contacted (via e-mail) just about every med comm company listed, with no results. I'm actually quite good at what I do, except at getting new business! Can you help?