All of those work. You will get many more No's then Yes's at first but when you get better at your cold calling, or your emails or your snail mails you will see better conversions.
One thing that can't be beat is networking. Businesses deal with other businesses on a daily basis. So if you can get close to one and maybe give them a bit off their work if they refer you some work, that will grow your business.
If you do good work it will snowball as businesses share with their buddies about their great new website and how they have noticed an increase in business and awareness. Other companies will want this product as they have to keep up or get left behind.
Another tip, represent yourself honestly but aim high! I mean, don't lie and say you are some big company to try and justify your rates. Let em know if your just starting out , everyone starts out at the bottom. But if you show that you have what it takes to get the job done, they will be inclined to hop on board before you are too successful and they can't afford you!
Most important... do not give your service away. It just hurts you in the long run. Ask for deposits on agreement of a job ( make sure you have contracts ready to sign at all times) and don't do a bit of work til you have seen some payment.
I can't tell you how many times I got hosed when I started out. I would bust ass, do a site expecting to be paid after it was done and then hear that their cousins, sisters, boyfriend is a computer whiz and is gonna do their site. Arrrrrrrgh!! What about my time?? Tough luck.
Good luck with you business!!