I've done it in the past, but I took a step back after I bought my home seven years ago. I kind of Forrest Gump'd my way into clients back then, but I know I cannot rely on luck and "word of mouth" alone to get new clients. I assume I'll find some luck by being more active in the networking events I sometimes attend, particularly if I gently inform the various people I know (and meet) what I do and find out what they do and what they need. What else might be helpful to know?
I like the phrase "Forrest Gump'd my way"; I'm using that from now on! :)
Honestly, that's kind of what happened to me. Since I started on the side while working a good-paying job, I just took a couple of clients that happened to fall into my lap. They referred me to some other clients, and one thing led to another. I did some networking and (very little) marketing or actively trying to get clients (other than telling all my clients, "I'm always open to new work, so if you need anything else or know someone who does..."), but I'd say that ~80% of my clients are there because they're part of the tree of clients that started with the first three that I lucked into early on. (Some of them are waaay down the tree, like client 1 referred client 2 who referred client 3 who referred client 4, and so on.)
If you aren't as lucky as I was, I'd give you two pointers:
1. Network, network, network - as you already know!
2. Find people who need your services and will pay for them. I have a friend who supports her family of four by blogging for companies. When I asked her once how she found clients, she said she looked for companies that already had a blog, but one that was not well-maintained. Then she approached them and said, "Hey, I can really make your blog work for you." She knew that if she approached companies that did not have a blog, they likely wouldn't see the value and pay for it, and those with well-done blogs may or may not hire her, but the sweet spot was those that needed her and had already seen the value of it. Not sure how that translates into your field, but that's the best advice I've ever heard about finding new freelance clients.
And no matter how you get the clients you get, the easiest way to get more freelance clients is to make your current clients happy. I have people who I've worked with for over a decade. They've moved companies, changed job titles, and they still call me up and say, "I've got something for you," several times a year. Not only will happy clients come back, they'll send you more clients.
How did you balance your time between work, freelance and anything else that happens? (For example, right now my girlfriend and I alternate weekends that we visit each other, as we live about 95 miles apart.)
I'm the worst person in the world to ask this of, because (like most entrepreneurs), I'm a workaholic. For a long time I was doing really long hours. (Actually, I'm doing about the same number of hours now, but it seems like so much less because I'm the boss!) But I would say, try starting like I did: find 3 hours in your week--just 3--to work on it. The place where I was working at the time, it was ok to take a lunch break (some places I worked, that was frowned upon). I would take my laptop to a nearby library (or sometimes just a corner of the building where my office was) and work during my lunch hour once or twice a week. I gave up a couple of television shows to find extra time to do it. I was passionate and determined to succeed, so I figured out how to do it. (Though, I'm not going to lie, it wasn't easy!)
At first, those three hours will be completely taken up with trying to find clients, getting a website up (if you don't already have one for your freelance biz), getting business cards, going to networking events, etc. Once you've got a project or two, you might find that you can up that 3 hours to 4 hours per week, and then to 5 hours, and so on.
Again, one of the things I found was that, as I started doing side projects, I had more energy and verve. Suddenly, I didn't mind working in the evenings when I got home from work because I knew that I'd be wiped out when I walked into the house, but after an hour of working on my freelance gigs, I'd be more mentally stimulated and happy. I'm not saying that I wasn't exhausted, only that I felt less zombie-like. It's kind of like the difference in being tired after running a marathon and being tired after sitting on the couch vegging out all day. For me, vegging out makes me feel sluggish and completely out of it, whereas running means I'm physically exhausted, but spiritually and mentally energized. The difference in the two is huge.
Sorry for the long post--hope it's helpful! Good luck to you!