Sometimes, people call you from out of the blue. Completely. There's absolutely no connection to an existing client, or personal friend, or cousin's ex-husband's business partner's mother's sister-in-law's lawyer*, or anyone else.
I just finalized a small job for a woman who I cannot for the life of me figure out how she knows I exist. But as I thought about it, there are actually many ways she could have found me. Maybe she was directed to my website by someone. Maybe she looked up the ATA database, or the NYCT database, and just started down the list. Maybe she saw an article I wrote for one of the ATA division newsletters. She could have even Googled "French translator Brooklyn", although I'm not entirely sure where I pop up on that list. Maybe someone threw one of my business cards away and the trash can fell over and my card happened to catch her eye. Who knows, really?
The point is, those are only a few ways that she could have found me. All of them are valid, and all of them are useful (except for maybe that last one with the garbage). I personally don't use every service available to me (I've almost given up on Twitter, I only spend limited time on LinkedIn, etc.), but apparently, all those avenues of promotion pay off. It's a nice ego boost to know you're doing something right.
*I will bake you cookies if you figure out who this person is in your life.