Knowing the quantity and quality of a given type of link opportunity in your keyword space will help you choose the right direction for your link building campaign. Here is a process for quickly querying your space to identify where the best opportunities are.
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Identify Your Top 3 Market Defining Keywords
Market defining keywords describe your entire market. They're usually not terms you target with paid search or even with your organic efforts. Traffic from these terms would be copious and low-converting. A camping goods retailer's MDKWs could look like: Camping, Hiking, and Outdoors. Starting with MDKWs - and not your profitable keywords - is vital for this exercise.
1) Check for Blogs
The presence of bloggers and the size of the blogging community in your keyword space will indicate whether or not your link building efforts should include blogger engagement such as group interviews and curated, well groomed "top blog post" aggregations such as this one.
Search Google with these queries:
MDFK blogs
MDFK "blog list"
"top MDFK blogs"
How many results in the top ten are relevant? Are you finding lists of bloggers? If not, make sure your MDFKs are broad enough! If so, then make note of "blogger engagement" as a solid direction for your link building efforts.
2) Check for News Sites and Trade Pubs
Industry news sites and trade publications are great places to establish relationships for the purpose of link building. Whether you're submitting news releases, how-to articles for publication or relevant comments in the discussion threads, news sites and trade pubs can be crucial to link building efforts.
Search Google with these queries:
"MDFK news"
MDFK "Trade Publication"
MDFK conference OR convention
What are you finding with these queries? The number of relevant results in the top 10 in Google should give you a good idea of whether or not this is a reasonable direction for you. In the case of the [conference OR convention] query you will have to trace the conventions back to their associated trade publications.
3) Check for Guest Post Opportunities
Guest posting and guest publishing are off shoots of a healthy publishing faction in your industry. If a person or organization is actively seeking content, this indicates a market. It also indicates an opportunity for you to build links and brand presence in your space.
Search Google with these queries:
MDFK "guest post"
MDFK inurl:category/guest
MDFK "guest article"
These queries should help you determine whether or not the publishers in your keyword space are actively seeking content. If so, then guest publishing could be a powerful way to build links, brand and targeted traffic.
4) Check for Interviews 
The presence of interviews signifies that there's an "expert class" within your keyword space. If there are a number of interviews then you should do two things. The first is seek to get thought leaders in your organization interviewed. Secondly you should conduct a group interview of all the experts who have received interviews.
Search Google with these queries:
MDFK intitle:interview
MDFK intitle:"q&a with"
MDFK intitle:"tips from" OR "advice from" OR "chat with"
These interview queries will demonstrate whether or not interviews are a solid direction for your link building and relationship growing efforts.
5) Check for Niche Directories 
Niche directories are almost always worth submitting to. Consider them a "covering your bases" link building effort. Some keyword spaces have niche directories and some don't.
Search Google with these queries:
"MDFK Directory"
"MDFK Websites"
MDFK "suggest * url"
Directory submission can help to align your site with targeted visitors, as well as provide a relevance and trust boost to your site within the major search engines.
6) Check for Niche Forums and Social Networking Sites 
What is the online community like in your keyword space? Remember, not everyone has caught up with "web 2.0," and there are hundreds of thousands of people perfectly happy with forums as platform for web interactions. Find them!
MDKW community
intitle:MDKW forum
MDKW inurl:blogs
Communities, if they exist, are excellent places to source content ideas as well as to build brand through contribution and interaction. Don't simply join to drop links - not only is this ineffective, but it will sour the community towards your organization.
7) Check for Professional Associations 
Professional associations indicate a high level of business organization within an industry. This means some great opportunities for link development. First off you should consider joining as a means of connecting formally with your industry. Secondly, many associations have online newsletters and publications that you can submit content to.
MDKW association
MDKW associated
MDKW intitle:"of america" (or other locale)
Professional associations, like many of the other link building opportunities on this list, can provide FAR MORE than just links. Dig in and see how you can get involved in the professional associations in your keyword space.
8 ) Resources for Deeper Querying 
If you strike a rich line of link opportunities along any of the above suggestions it's likely that you could build an entire campaign around developing links and relationships from those sources. First though, you will need to query more deeply along those lines. We recommend the following tools and resources for developing out your query list.
21 Link Builders Share Advanced Link Building Queries
SEOBook Link Suggest Tool
Link Search Tool by SoloSEO
the Ontolo Link Building Query Generator
Garrett French is the co-founder of Ontolo, Inc., creators of the Ontolo Link Building Toolset which uses your target keywords to find and grade link prospects. The Link Building Toolset reduces link prospecting and qualification time, letting you focus on the most important part of link building: relationships.