There are many ways to do link building for SEO purposes, Here I am going to talk about then a little bit.
Great content: Obviously generating great content is the best way to get good quality organic links. People will share your content and you will get good links for free.
Controversy: I do not know if this is the best way to get links, But if definitely one of then.
Participate on the community: Answering questions in forums is a great way to link back to your website and at the same time helping the people aut there that could be your future client.
Original research: If you research a subject in deep, you will end up with great information to make an article to help people on the subject and at the same time create great content that people will use and share.
Social Media: participate on the community, give away what the people is looking for. share stories, funny things that people want to share.
Newsletter: Create a newsletter with useful resources.
Conference presentation: Give a presentation on your local library.
Good piece of advice:
- Have a resource on your website that nobody has.
Service that people find useful.
- open source.
- free templates.
- extension for Firefox, chrome, or other browser.
- Free app.
- wordpress plugin
Following is a video by Matt Cutts from Google talking about Link building strategies: