Use the Google Adwords Keyword Planner to find new and related keywords, but ignore the search volume data! The search volume data in the planner is really only useful for keywords that you’re actually spending money to advertise on. Otherwise, these volumes are not reliable. While not really helpful to decide which keyword is most used by your potential audience, Google Adwords Keyword Planner makes a useful tool in coming up with ideas for potential keywords!

The link back to googles API is crap – it keeps coming up with password authentication which renders it virtually useless when trying to find your own rank. Sells you the software initially. But then tries to sell you a load of stuff afterwards which effectively tells you the first version you have already paid for is useless without the extra “bonuses”. Not a nice way of doing business
From time-to-time – there are discounts or promotions available for Long Tail Pro. Whenever these become available – all links on my site that lead to the Long Tail Pro sales page will reflect the discounted price. If there is a huge sale or a massive deal – I always let my email subscribers know about it as soon as possible. If you’re not on my email list yet – feel free to sign up by clicking the button below. I’ll even send you one of my FREE guides!
For a long time, I wanted to develop a tool for content marketers that would assist in the process of coming up with blog ideas and subjects. Upon researching developers for this concept I had, I stumbled across  Long Tail Pro, and realized instead of developing a tool myself for fellow bloggers and content marketers, I would throw my support behind this one.
Most people who use the Google’s auto complete feature to generate keywords that they include in their blog title or page find Soovle to be a very useful tool. This tool moves the auto complete feature a step forward by getting inputs from several sources like Amazon, Yahoo, Wikipedia, Bing apart from Google itself. This assists the user to generate keywords that drive online traffic in a better way. The default is usually set to Google but you can switch to the other options at your own will and view how the outcome keeps on changing. You can experiment with a broad range of keywords by running them through a specialized tool such as the keyword inspector as a way of extracting value that will boost your sales on Amazon.
Google Suggest isn’t exactly a tool, but I’ve found that it can be useful for identifying potential keywords. As you type a query on, Google Suggest recommends search queries based on other users’ search activities. These searches are algorithmically determined based on a number of purely objective factors (including popularity of search terms) without human intervention. The Suggest dataset is updated frequently to offer search queries that seem to be trending upwards. This feature is largely one of the reasons that you may see repeat traffic of seemingly long tail keywords. By identifying these long tail keywords and optimizing for them, marketers can capitalize on seemingly obscure keywords with little competition.
Search Analytics can be found under the 'Search Traffic' section and provides details of the keywords that drove clicks to your website, based on data for up to the last 90 days. The difference with Google's version is that you can filter the data to put extra context around the keywords, such as filtering by country to see keyword popularity based on country, which can be useful when carrying out keyword research for websites that service more than one country.
Offer Details: Offer expires 9/30/2018 (midnight Pacific Time), and is available only to qualified advertisers who meet the following eligibility criteria: Open to new and verified Bing Webmaster Tools account holders who own their own Website and open a new Bing Ads account; a “new” account is one that has been open fewer than 30 days prior to the date of coupon redemption. Your account will be evaluated daily to verify you meet the eligibility criteria. When criteria is met, a Bing Ads coupon will be sent to each qualified advertiser by email in approximately 3 business days from date of verification. See full offer details here.

Let's say you're considering starting a new website, or venturing into a new product niche. And, suppose you'd like to somehow determine how much search buzz is currently hovering around this topic. You can use Keyword Researcher to get a "feel" for how much interest is actually out there. For example, let's say you were selling cameras. Then you might consider the following:
So which tool should you use? The simple answer is ALL of them!! If the data from several tools suggests that a keyword may be a good keyword to target, than you should feel fairly confident that it is. If your results appear to be contradicting one another for a particular keyword, then you may want to be hesitant in including that keyword in your selection. SEO professionals should never rely on one resource for research. No one tool is going to be 100% accurate and you stand the best chance at making the correct strategic decisions by using a variety of sources.
Understanding which websites already rank for your keyword gives you valuable insight into the competition, and also how hard it will be to rank for the given term. Are there search advertisements running along the top and right-hand side of the organic results? Typically, many search ads means a high-value keyword, and multiple search ads above the organic results often means a highly lucrative and directly conversion-prone keyword.

The limit on manual keywords could be higher.  I personally wish we could input 10,000 keywords at a time, instead of 200.  However, I understand the costs that Long Tail Pro has to maintain each time a new manual keyword is input.  Not a deal breaker, I just wish the limit was higher. (To be fair, I don't think most keyword tools have a bulk manual option at all).