I don't have a direct answer for your questions about links, but you also seem to asking about content.
In terms of content, I'd take a look at content marketing, and I think you might be surprised at the potential.
In particular, I recommend the book Epic Content Marketing by Joe Pulizzi. He had a really interesting example about a company that sells/installs Fiberglass Pools called River Pools and Spas (that serve 3 eastern states). The company runs a blog that answers questions about all pools, and they brand it "Welcome to the Most Educational Swimming Pool Blog in the Country!" Ofc, they focus a special amount of time on pitching fiberglass pools. According to the interview in the book, the blog does quite well for them. Notice that they broaden their content (a) to include slightly beyond what they sell, and (b) beyond their geographical scope.
Look at it a different way: our company recently had to rent out a forklift company, and we Google'd for answers to my questions about renting forklift. I'm sure many others have questions for forklifts. I'm sure there are similar potential for questions about accounting/tax/financials, construction/concrete/etc.