Backlink Resources From Beginning To End

I have been looking for some good resources on backlinks. I have been having issues doing this in the past and I finally want to conquer backlinks. I understand a lot of the basics, but backlinks have always been a little trickier for me to understand with the google updates and also I don't want to use Fiverr anymore for a site that is important. I'd rather just do it myself and gain the experience firsthand. I looked through the forum but couldn't find some definitive guide on them, I don't know if there is. I have done competitor analysis already and most of my competitors backlinks are from their business partners or paying for links from outdated directory listings.

Any updated info on backlinks that helped you guys out, or a guide somewhere?

Thanks