There are community forums setup online for virtually every niche, industry, or topic you can imagine. The internet is a prime place for like minded people to talk to each other. 9 times out of 10 you can find a forum for your industry just by typing in [your industry]forum.com or searching for “[Your Industry] Forum” on Google. Find the forums in your industry with the largest user base, start posting there and become an active community member. Most forums will allow you to leave a link to your website in your post signature, so the more you post the more traffic you get.
Companies that employ overly aggressive techniques can get their client websites banned from the search results. In 2005, the Wall Street Journal reported on a company, Traffic Power, which allegedly used high-risk techniques and failed to disclose those risks to its clients. Wired magazine reported that the same company sued blogger and SEO Aaron Wall for writing about the ban. Google's Matt Cutts later confirmed that Google did in fact ban Traffic Power and some of its clients.
This post and the Skycraper technique changed my mind about how I approach SEO, I’m not a marketing expert and I haven’t ranked sites that monetize really well, I’m just a guy trying to get some projects moving on and I’m not even in the marketing business so I just wanted to say that the way you write makes the information accesible, even if you’re not a native english speaker as myself.