Forums are a good way to build up a portfolio. Enter as many contests as you possibly can, and even if you don't win you can add your creations to your portfolio. You could even ask the intended client for feedback on your design which you could put alongside it in your portfolio.
The webdesign industry is over saturated, you will find huge amounts of designers online, but more often than not companies near your house (just take a walk down the street) don't muse the internet. Print some flyers and business cards and ask for a few minutes of their time or just ask to leave a business card with them.
Confidence is the key, and even if they don't buy into it they might pass it on to a friend.
Always carry business cards around with you, you never know who you might bump into and they could possibly be interested in your services.
Regards,
Jonny.