I also want to emphasize that Microsoft Excel and Google Docs perhaps play an equal, if not more important role in keyword research than any of these tools, because at the end of the day, the mountain of data you end up with is of no use if you can’t perform calculations, sort, filter, present or store it in a way that’s best suits the task at hand. Head over to Distilled for a comprehensive Excel for SEOs guide. Alternatively, bug this guy—he’s the Sensei who trains Excel ninjas in the dark of the night.
You can filter your results by 24 business verticals, including Apparel, Arts & Entertainment, Autos & Vehicles, Beauty & Fitness, Books & Literature, Business & Industrial, Computers & Electronics, Finance & Banking, Food & Drink, Toys & Games, Health, Hobbies & Leisure, Home & Garden, Internet & Telecom, Jobs & Education, Law & Government, News Media & Publications, Family & Community, Occasions & Gifts, Pets & Animals, Real Estate, Retail & General Merchandise, Sports & Fitness, and Travel & Tourism.
If you are looking for keywords in languages other than English, you will find Keyword Tool's features very useful. Keyword Tool allows you to pull keywords from 192 Google domains and use 83 Google language interfaces to generate keyword suggestions. That way we make sure that the generated keywords will be relevant to the country and/or language that you are creating your content for.
Trying to rank for the keyword “Best Headphones” will see your post, page, or article buried in the depths of a billion search engine pages, and it’s never going to surface in the top thousand pages, let alone page one…ever! But going for a keyword, or Long Tail keyword phrase “What are the Best Headphones for Sleeping” will stand you in better shape to get somewhere close, or even on, the first page.
Note: the old software version of Long Tail Pro would have spit out several hundred adwords suggestions (many being irrelevant to the seed keyword) for this one seed keyword and then you would have to filter to see only what you wanted to see. With the new cloud version of Long Tail Pro, you set it to show only a certain number of keywords and it displays the most relevant keywords so you have less noise and confusion to filter through.
A service like BrightEdge comes with the biggest costs associated, but its SaaS solution for SEO covers many areas inside of a single ecosystem, including the ability to explore keyword data. This may be a benefit for agencies that wish to reduce redundancies across vendors, but eventually, it is likely that the need for a second tool will present itself as talent and effort levels increase inside of your SEO department.
Repeat this exercise for as many topic buckets as you have. And remember, if you're having trouble coming up with relevant search terms, you can always head on over to your employees on the front lines -- like Sales or Services -- and ask them what types of terms their prospects and customers use, or common questions they have. Those are often great starting points for keyword research.
3. Finally, there's just good old research through trends and news. Google Trends, keeping up on industry news of the business, and even newsjacking (if there are relevant topics). These all require different resources depending on the business, but once you find the leaders in their news you can not only leverage them for keyword research but also glean insights into how you can become an industry leader yourself (and dominate SEO).