Promoting your website is easy. Basically, all I do to refer others to my site, is sit in my lazy chair in front of my tv, with my feet out, watching movie after movie, while chatting on forums on my laptop. That's really what I do, and that's all you have to do.
Forums are a very effective way of promoting. There are practically an unlimited number of forums out there, on basically any subject you'd want to chat about. And some forums are so large, that you could spend all day just chatting in all the various sections.
I am not saying that you should spam the forums, talking about your website. Use your sig file. If you just push your website, you'll get very poor results, besides getting banned. Try to keep to the subject at hand. If the forum is about gardening, talk about gardening. Find something you enjoy talking about, and chat away. Everytime you make a post, you leave your mark, with your sig. Others will see it over and over again, even days later, when they're viewing that thread.
You want to earn a nice reputation over time, and build up your post count, by making intelligent conversation, not meaningless posts just to spam your sig. Take your time, and enjoy the chat. It's not a hard living. You'll develop trust with other member's of the forums, even make a few friends, and then people will be interested in what you have to say in your sig. You'll probably get some PMs, and have plenty of opportunity to talk about it, at the right time. Earning money with your computer is a very hot subject these days. If you make nice posts, and have a good sig, you'll spark plenty of interest.
Just try to be real. The more artificial you are, the less your result will be. This is really all you have to do, and you can earn a lot of money very quickly by doing this.