For good link building and SEO, you need to build good relationships. There are plenty of opportunities to build new contacts. You should start with niche-related communities: forums, blogs or social groups.
Make the first step and start contributing with interesting and relevant comments and posts, providing contextual value to each discussion.
By actively participating in these online communities focused on your niche, you will not only gain some good backlinks, but you will always have access to the newest industry news and be able to connect to some interesting people that share your passions.